GENEVA (Reuters) - The World Trade Organization said on Tuesday it is reviewing staff costs after the United States paused funding to the institution.

Reuters reported on March 27 that the U.S., the top donor to the WTO budget, had paused its contributions including unpaid dues for 2024 pending a review of its support to international bodies - in a move confirmed by the U.S. government.

Since then, trade sources told Reuters that WTO staff had been informed about incoming measures to reduce spending such as not replacing some retiring staff or short-term hires.

The WTO, which has 630 staff, said that it has no plans for fixed and regular staff reductions at this time.

"In a recent town hall, the Director-General (Ngozi Okonjo-Iweala) informed staff that in response to the current financial climate, Senior Management is exercising fiscal prudence by curtailing or deferring expenditures as necessary," WTO spokesperson Ismaila Dieng said in response to Reuters' questions.

He added that a newly formed 'Staffing Resource Needs Committee' would review vacancies and related expenditures.

The measures come against a backdrop of recent U.S. criticism of WTO spending and five years after its top court was paralysed under Trump's first term, amid U.S. concerns about overreach.

A U.S. delegate previously raised budget concerns about a meeting to mark the 30th anniversary of the organisation which is now grappling with the impact of U.S. President Donald Trump's tariffs on global trade.

Washington will also raise "systemic concerns" about the WTO's actions at a meeting on Wednesday, an agenda document showed.

"... It has become readily apparent that the (WTO) Secretariat is moving away from its Member-driven purposes, and is attempting to re-invent itself into a resource to be provided to the public, regardless of Members' views or the impact that such activities may be having on Members' interests or budget contributions," a U.S. delegation document showed.

The WTO budget of 205 million Swiss francs ($239.99 million)is smaller than many other global bodies, some of which have been badly hit by Trump's spending cuts.

Delegates say that it would theoretically be easy for any one of the WTO's 166 members to entirely block the next budget later this year since such decisions must be taken by consensus.

A spokesperson for the U.S. mission in Geneva did not immediately respond to a request for comment.

($1 = 0.8542 Swiss francs)