North Korea’s top diplomat to the United Nations has accused the U.S. of fabricating lies that Pyongyang had been diverting U.N. aid money to develop nuclear weapons.

In a letter to U.N. Secretary-General Ban Ki-moon, Pak Gil-yon said his country would accept an outside audit of U.N. operations, stressing that U.N. aid projects in the North have been carried out in a fair and transparent way in line with U.N. regulations.

Pak said the North wants to continue cooperation with U.N. agencies, citing that Pyongyang has maintained “good relations and cooperation” with them for several decades.

Pak was quick to add, however, that if the proposed external audits seek to serve the alleged U.S. attempt to politicize international aid to the North, Pyongyang would not tolerate it and the consequences would be severe.

In January, the U.S. accused the U.N. Development Program (UNDP) of operating in violation of U.N. rules and providing the North with hard currency.

The UNDP suspended nearly 18 million dollars in budgeted funds for its operations in the communist state following the outcome of a 90-day investigation.