The United States will no longer shoulder more than a quarter of the costs of the United Nations’ peacekeeping operations, Washington’s envoy has said.

“Peacekeeping is a shared responsibility,” US Ambassador Nikki Haley said at a Security Council debate on peacekeeping reform. “All of us have a role to play, and all of us must step up.”

The US is the biggest contributor to the UN’s 15 peacekeeping missions worldwide. Washington is paying about 28.5% of this year’s 7.3 billion US dollar peacekeeping budget, though Mrs Haley said US law is supposed to cap the contribution at 25%.

The second-biggest contributor, China, pays slightly more than 10%.

President Donald Trump’s administration has complained before that the budget and the US share are too high and pressed to cut to this year’s budget. It is 570 million dollars below last year’s, a smaller decrease than Washington wanted.

“We’re only getting started,” Mrs Haley said when the cut was approved in June. It followed a 400 million dollar trim the year before.

Mrs Haley said the US will work to make sure cuts in its portion are done “in a fair and sensible manner that protects UN peacekeeping”.

The General Assembly sets the budget and respective contributions by vote. Spokesmen for Assembly President Miroslav Lajcak and UN Secretary-General Antonio Guterres declined to comment on Mrs Haley’s remarks, noting that the peacekeeping budget will be up to the 193 member states to decide.

Drawing 105,000 troops and other personnel from countries around the world, the peacekeeping missions operate in places from Haiti to parts of India and Pakistan, though the bulk of the operations are in African countries.

The biggest is in Congo, where the Security Council agreed on Tuesday to keep the 16,000-troop force in place for another year.