Here are international treaties: explained.  

There have been a few international treaties, like the High Seas Treaty or the Global Plastic Treaty, that impact the Ocean, but in a world of complex language and changing timelines, we wanted to make the process make sense.  

The start of any treaty: Agreeing there is an issue 

The first thing to understand is that the process of international negotiation is rarely a quick one. One of the fastest processes was the Montreal Protocol, the treaty to protect the ozone layer, which moved from initial scientific discovery (1973) to being signed (1987) in just 14 years.  

The process of an international treaty is kicked off by proposal – a member state, or more commonly a group or coalition of states, can introduce a resolution to a governing body (such as the UN General Assembly, the UN Environment Programme etc.).  

This step is about agreeing there is a problem that needs solving.

The mandate: Permission to negotiate 

So, we’ve agreed – we have a problem that needs solving. The UN governing body adopts (votes on and approves) the resolution, which is a statement of intent.

The mandate will decide the scope of the agreement – is it going to make a legally binding agreement or a voluntary one, a regional or international?  

This gives the mandate to begin negotiations.  This usually means creating a committee for international negotiation – an International Negotiating Committee (INC) if you will.  

Then the fun begins.  

The hard part: Reaching consensus with negotiations 

The INC will have a series of meetings, attended by states and “observer” parties – non-governmental organisations, industry groups and scientists amongst others.  

In these meetings, they will negotiate the text of the agreement. Wording is crucial, especially for a legally binding agreement, so agreeing a draft text is usually the longest stage.  

This stage is ended when consensus is reached: the vast majority of parties are happy with the contents and phrasing of the text. The text would then be adopted (voted on and agreed, in treaty language) and is open for signatures and ratifications.  

What does it mean to sign or ratify a treaty? 

States can sign an agreement or ratify it. Signing it is an announcement of intent, it isn’t binding but it shows that a state intends to ratify. They will often sign as a placeholder while the relevant domestic processes are taken.  

Ratifying is the full involvement (legal obligation) to the agreement, whatever it may say.  

Most agreements will have a minimum number of ratifications before it comes into effect. Once enough states have ratified, the treaty will become reality. States can ratify after the treaty is in effect – latecomers are always welcome.  

Implementation: From agreement to action 

Once the treaty exists, a Conference of the Parties (COP) or Meeting of Parties (MOP) will take place to oversee progress, amendments and compliance. The regularity of meetings varies.  

How collective decision-making works: A practical example 

Imagine you live in a house with a number of other people and the heating breaks.  

First, one (or more) of you could raise this in the house group chat. You present evidence of the issue (the heating doesn’t come on, and the house is cold). Some housemates may have a warm room, and don’t agree initially. More evidence may be required – bring in a GP to talk about increased risk of illness or put some thermometers around the house. 

When the housemates agree the heating is broken, and they would be better off if it was fixed, they agree to have a house meeting (or five) to discuss how to go about fixing it.  

Is it a plumbing issue or an electrical one? Who should pay for it? If one housemate uses the heating all the time while others use less, should they pay more? To avoid future heating problems, what should the temperature be set at? This happens at the pub so, it takes a while.

Then, the plan is all sorted, but to get the ball rolling everyone needs to give a go-ahead. Five out of seven thumbs up in the group chat is the green light.  

It may take a couple months while people save from their pay checks, but finally there are five thumbs up and the heating can get fixed.  

The last two were grumbling about the hot water use but gave the thumbs up later on so they can use the heating.  

Success Story: How the Montreal Protocol was created to protect the ozone layer 

The Montreal Protocol is one of the biggest wins in international cooperation. In the 1970s, scientists Frank Sherwood Rowland and Mario Molina started to hypothesise that chlorofluorocarbons (CFCs) were depleting the ozone layer.  

CFCs were a replacement for toxic refrigerants used in the 1920s, developed in the lab. They were used in aerosol sprays and any units needing refrigerant – refrigerators, air conditioners, cars, water chillers, for example.  

The depletion of the ozone layer was shown to result in an increase in UV-B radiation, leading to higher rates of skin cancer and damage to crops and marine phytoplankton (the little guys producing over 50% of our oxygen).  

Aerosol and halocarbon industries lobbied against regulation. A board member of a company with 25% market share in CFCs, was quoted as calling the hypothesis, “a science fiction tale…a load of rubbish…utter nonsense”.  

The treaty text was agreed on 16 September 1987, with the condition that it would come into force if 11 parties had ratified by 1 January 1989. 

It met this condition and has since been ratified by all 198 parties in the UN, becoming the first treaty to do so.  

Since the treaty, the ozone layer has been recovering and is projected to reach 1980s levels between 2040 for most of the world and 2066 for Antarctica.  

Post by

Will Steen

The Global Plastics Treaty refers to the (currently undefined) international agreement by which the countries of the world hope to reduce plastic pollution. 

How far have we got? Progress in the Global Plastic Treaty talks. 

In 2022, 175 countries of the world signed an agreement that declared: plastic pollution needed to be addressed. Stronger than that, plastic pollution should be ended.  

To meet this goal, countries agreed on a series of meetings across the globe to discuss and negotiate how to end plastic pollution and write it into international law (a treaty). 

Five meetings were planned, with the treaty aimed to be finalised by the end of 2024.  

This agreement created the International Negotiating Committee (INC) which first met in Punta del Este in Uruguay. Subsequent meetings happened in Paris, France; Nairobi, Kenya; Ottawa, Canada; and Busan, Korea. 

By the end of the fifth meeting, no agreement had been reached for the Global Plastics Treaty, so another (INC5.2) was scheduled for August 2025 in Geneva. However, this meeting also ended with no treaty. 

What is stopping a treaty being agreed? 

For the treaty to come to life, all countries must agree on the terms, so while some disagree there will be no treaty.  

The main point of disagreement is whether making new plastic (plastic production) should be limited within the treaty. Countries are split largely into two groups, the High Ambition Coalition and the Global Coalition for Plastics Sustainability. 

What is the High Ambition Coalition?  

There is a large group of countries (around 100) in a group, called the High Ambition Coalition (HAC).  

The HAC has been pushing for the plastics treaty to include plastic production limits – reducing the amount of new plastic made. Before INC5.2 the HAC published a “wake-up call” at the United Nations Ocean Conference at Nice in June 2025, outlining a ‘wishlist’ of five points: 

• Limits on plastic production (to be regularly adjusted), and reporting on production, import and export of primary plastic polymers 
• Phase out most harmful plastic products and chemicals of concern 
• Improve the design of plastic products to minimise environmental and human impacts 
• Financial support to support less developed countries in the transition 
• A treaty responsive to changes in evidence and knowledge 

What is the Global Coalition for Plastics Sustainability? 

Another group of countries formed the Global Coalition for Plastics Sustainability (also known as the Like-Minded Group of Countries).  

A statement from a member country outlined the focus: 

“The [Global Plastics Treaty] should pave the way for improving the waste management systems in general, and to promote environmentally safe and sound management of hazardous plastic wastes, and to reduce uncontrolled hazardous plastic pollution.” 

They want a bottom-up approach, prioritising dealing with plastic waste.  

What do major businesses think of the plastics treaty? 

Businesses that produce and use plastic are key to tackling the plastic pollution problem. 

The UK hosted a roundtable with major business in June 2025 and produced a statement. It called for the plastics treaty to address the whole lifecycle of plastics, amongst other things. 

“As businesses and financial institutions, we stand ready to mobilise significant investments, and engage with the companies we invest in, towards achieving the objectives of the legally binding instrument, including towards innovation and infrastructure.” 

Other businesses, such as fossil fuel companies (99% plastics are made from fossil fuels) take a different view:  

“While there have been calls for production caps or bans, it’s been reassuring to hear leaders share their belief that such measures could deprive the world – particularly the developing world – of the untold benefits plastics deliver in terms of health, food safety, the environment, the energy transition and more.” – Exxon Mobil President  

What’s next for the Global Plastics Treaty? 

The division has been entrenched from early in the process, with little movement on either side. It has led to questions about the process, and where to go next. Here are some options: 

1. The process is changed to being decided by vote rather than by consensus, to make progress despite the disagreement of a small minority 
2. The process continues via other means. For the Ottawa convention on landmines, a number of countries compiled texts outside of the process, that were then agreed upon. We could see this happening, for example, with the High Ambition Coalition.
3. Another round: INC5.3 to try again! A (currently unnamed) country has offered to host, but has said they will not fund it. 

While the gears of global negotiation can feel like they turn slowly, they are turning. Read more about how international treaties work here. 

These countries have agreed that ending plastic pollution is an important issue. We want a world without the damage of plastic pollution.  

The Global Plastics Treaty is the representation of international intent. If it does produce legal guides to end plastic pollution, it will speed up progress. That it hasn’t yet is not going to stall momentum.  

Plastic pollution is an international target.  

Post by

Will Steen