President Reagan is releasing $188 million in overdue U.S. payments to the United Nations after becoming convinced that the world body has reformed some administrative and budgetary procedures.

At the same time, the White House said Reagan told the State Department to work out "a multiyear" repayment plan involving some $520 million in arrearages that have piled up in recent years because of U.S. dissatisfaction with the way the U.N. was run."In announcing these decisions, the president called on the United Nations to continue progress in areas where reform remains incomplete," spokesman Marlin Fitzwater told reporters Tuesday.

"The president reiterated the commitment of the U.S. to assist the U.N. in its reform program as well as in its new peacekeeping efforts," he said.

In addition to the roughly $520 million in late dues payments, the United States is in arrears to the tune of $111.8 million in the assessments it is supposed to pay toward the separate U.N. peacekeeping budget.

The United States pays 25 percent of the cost of running the United Nations and 31 percent of the cost of the peacekeeping operations.