The United Nations is running a deficit of $230 million, Secretary General Antonio Guterres warned on Monday, and may run out of money by the end of October unless world governments immediately meet their financial obligations.

U.S. taxpayers would most likely be hardest hit by any immediate cash injection into the global organization.

The United States is by far the U.N.’s biggest financial contributor, providing 22 percent of its operating budget and funding 28 percent of peacekeeping missions, which currently cost $8 billion annually.

The next two major contributors are Germany and the U.K.

In a letter intended for the 37,000 employees at the U.N. secretariat and obtained by AFP, Guterres said unspecified, “additional stop-gap measures” would have to be taken to ensure salaries and entitilements are met.

These might include holding fewer meetings and cutting back on travel and associated entitlements.

“Member States have paid only 70 per cent of the total amount needed for our regular budget operations in 2019. This translates into a cash shortage of $230 million at the end of September. We run the risk of depleting our backup liquidity reserves by the end of the month,” he wrote.

Donald Trump has long pushed for reform of the U.N. and just last week warned the “future does not belong to globalists” in a warning to the organization’s leaders:

In December 2017 Nikki Haley, the then United States Ambassador to the organization, announced the federal government had reduced its contribution to the U.N.’s annual budget by $285 million, as Breitbart News reported.

Haley’s statement came after the U.N. voted to condemn the United States for President Donald Trump’s decision to recognize Jerusalem as the capital of Israel. The resolution, backed by nations with long records of extreme human rights abuses, passed 128-9. Haley immediately responded by threatening to reduce America’s U.N. funding.

“The United States will remember this day in which it was singled out for attack in the General Assembly for the very act of exercising our right as a sovereign nation,” Haley told the assembly in New York City.

“We will remember it when we are called upon to once again make the world’s largest contribution to the United Nations and we will remember it when so many countries come calling on us, as they so often do, to pay even more and to use our influence for their benefit.”

AFP contributed to this story