US President Donald Trump has signed a memorandum directing the withdrawal of the country from dozens of international organisations, including UN agencies, the White House said.

"Today, President Donald J. Trump signed a Presidential Memorandum directing the withdrawal of the United States from 66 international organisations that no longer serve American interests, including: 35-non UN organisations, 31 UN entities," the White House said on Wednesday.

The White House did not list the organisations but said they promote "radical climate policies, global governance, and ideological programs that conflict with US sovereignty and economic strength."

It said the move was the result of a review of all international intergovernmental organisations, conventions and treaties that the US is a member of or party to.

"These withdrawals will end American taxpayer funding and involvement in entities that advance globalist agendas over US priorities, or that address important issues inefficiently or ineffectively, such that US taxpayer dollars are best allocated in other ways to support the relevant missions," the White House said.

Since beginning his second term a year ago, Trump has sought to slash US funding for the UN, stopped US engagement with the UN Human Rights Council, extended a halt to funding for the Palestinian relief agency UNRWA and quit the UN cultural agency UNESCO. He has also announced plans to quit the World Health Organization and the Paris climate agreement.