LONDON (AFP) - The United Nations sexual and reproductive health agency UNFPA on Thursday (April 29) said Britain's "devastating" plan to slash its annual funding would lead to some 250,000 more deaths around the world.

Britain has told the UNFPA that it will implement an approximate 85 per cent cut to the agency's flagship programme for family planning, contributing £23 million (S$42.55 million) this year instead of its original commitment of £154 million.

"These cuts will be devastating for women and girls, and their families across the world," UNFPA said in a statement.

"With the now-withdrawn £130 million, the UNFPA Supplies Partnership would have helped prevent around 250,000 maternal and child deaths, 14.6 million unintended pregnancies and 4.3 million unsafe abortions."

The agency acknowledged "the challenging situation facing many donor governments", but said it "deeply regrets the decision of our longstanding partner".

"The truth is that when funding stops, women and girls suffer, especially the poor, those living in remote, underserved communities and those living through humanitarian crises," it said, adding that it was "actively formulating mitigation strategies".

Britain says it needs to trim its legally enshrined aid budget to cope with the coronavirus pandemic.

Emergency pandemic support measures have sent Britain's annual borrowing rocketing to its highest level since World War II, official data showed last Friday.