The United States has announced that it had united with the European Union and 79 developing countries to jointly push for an ambitious accord in Paris to curb global warming. The decision, announced by US Secretary of State John Kerry, came a day after the European Union said it had joined the African, Caribbean and Pacific nations most vulnerable to climate disasters to lobby for a far-reaching deal. However countries within the alliance dubbed the “high ambition coalition” by the United States have conflicting aims on some key points in the accord.

India—which has baulked at accelerating the review of carbon-cutting pledges and at setting the decarbonisation of the global economy as a goal—is not part of the coalition. Nor are economic giants China and Brazil.

Alden Meyer, climate change expert at the Union of Concerned Scientists, said the grouping started informally in July. The emergence of a coalition among those most determined to make deep and verifiable emissions cuts may be seen as a sign that deep divisions remain as the delegates battle to put together a final deal.

Illustrating the complexities at play in Paris, many of the developing nations in the “coalition of ambition” remain in an official negotiating bloc that includes China, India and Brazil known as the G77. In the lead-up to Paris, the United States has also been engaging with all major powers.