UNITED NATIONS - The United Nations has not yet received any official notification from the United States regarding the latter's decision to withdraw from 31 UN entities, a UN spokesperson said Monday.

"No," Stephane Dujarric, spokesperson for the UN Secretary-General Antonio Guterres, said at a daily briefing.

The United States is to withdraw from 66 international organizations, according to a presidential memorandum signed by US President Donald Trump on Jan. 7. The memorandum applies to 31 UN entities and 35 non-UN entities, which the White House said "no longer serve American interests."

In a statement issued by the spokesperson on Jan 8, the UN chief regretted the US announcement by the White House.

"As we have consistently underscored, assessed contributions to the United Nations regular budget and peacekeeping budget, as approved by the General Assembly, are a legal obligation under the UN Charter for all Member States, including the United States," the statement said.

Noting that all UN entities will go on with the implementation of their mandates as given by member states, the statement said the United Nations "has a responsibility to deliver for those who depend on us. We will continue to carry out our mandates with determination."