The United Nations will cut a quarter of peacekeepers in 11 operations around the world in the coming months due to a lack of money, senior U.N. officials said on Wednesday, and as future funding from the United States remains uncertain.

"Overall, we will have to repatriate ... around 25% of our total peacekeeping troops and police, as well as their equipment, and a large number of civilian staff in missions will also be affected," said a senior U.N. official, speaking on condition of anonymity.

That would amount to between 13,000 and 14,000 troops and police, the official said.

Washington is the U.N.'s largest peacekeeping contributor, accounting for more than 26% of funding, followed by China, which pays nearly 24%.

These payments are not voluntary.

The U.S. was already $1.5 billion in arrears before the new fiscal year began on July 1, said a second U.N. official.

Washington now also owes an additional $1.3 billion, taking its total outstanding bill to more than $2.8 billion.

The U.S. has told the U.N. it will make a payment shortly of $680 million, the first U.N. official said.

The U.S. mission to the U.N. did not immediately respond to a request for comment.

President Donald Trump in August unilaterally canceled some $800 million in peacekeeping funding appropriated for 2024 and 2025, according to a Trump administration message to Congress.

The White House budget office has also proposed eliminating funding for U.N. peacekeeping missions in 2026, citing failures of operations in Mali, Lebanon and Democratic Republic of Congo.

The U.N. has peacekeeping operations in the Middle East, South Sudan, Democratic Republic of Congo, Lebanon, Kosovo, Cyprus, Central African Republic, Western Sahara, the Golan Heights demilitarized zone between Israel and Syria, Abyei — an administrative area jointly run by South Sudan and Sudan — and on a ceasefire line dividing Kashmir between India and Pakistan.

U.N. Secretary-General Antonio Guterres is also more broadly seeking ways to improve efficiency and cut costs as the world body turns 80 this year amid a cash crisis.