The UK is to give £3m to organisations denied US aid for providing safe abortions in developing countries.
US President George Bush imposed the "global gag" rule in 2001
International Development Minister Gareth Thomas said he hoped the move would persuade other nations to step in and help prevent thousands of deaths.
The World Health Organisation estimates backstreet abortionists cause 70,000 "agonising" deaths every year.
But to receive US aid, health clinics must pledge neither to provide abortion services nor advise women to have one.
Since US President George W Bush imposed this so-called "global gag" rule in 2001, the International Planned Parenthood Foundation (IPPF) has had to close dozens of clinics.
But with Britain's £3m it will set up the Global Safe Abortion Programme to improve access to safe abortion services and "support other partners that have had to cut back on reproductive health services because of the impact of the gag rule".
The IPPF says 19 million women can be spared serious injury, illness or death if safe and legal abortions are accessible alongside other health services.
At present, 13% of maternal deaths worldwide are due to unsafe abortions - 60% in some countries.
The United Nations has set a target to reduce overall maternal mortality by 75% by 2015, as part of its Millennium Development Goals.
Mr Thomas called on the US to drop its funding ban, but he said: "It is not likely to be lifted in the short term and the Global Safe Abortion Programme and our funding to it is a response to that situation.
"The absence of sexual and reproductive health services results in an increase in unintended pregnancies and, inevitably, a greater number of unsafe abortions," Mr Thomas told BBC Radio 4's Today programme.
IPPF director general Steven Sinding said: "The UK is being very brave and very progressive in making this commitment.
"We are deeply grateful for this gesture - not only financially, but also politically.
"What I have never been able to figure out about American policy is why they persist in cutting down funding to organisations that are about preventing unwanted pregnancies.
"Tens of thousands of women who depend on our services are not able to get them.
Mr Sinding added: "We are committed to the expansion of safe abortion because in any society no matter how efficiently contraception is made available there will be unplanned and unwanted pregnancies."
But anti-abortion groups have expressed anger at the announcement.
The Society for the Protection of Unborn Children (SPUC) called the move an "attack on the demographic of developing countries".
A SPUC spokesman said: "The last thing a wealthy and supposedly civilised country should be exporting to the developing world is its anti-life culture."
He said aid efforts should instead focus on "protecting life" through promoting "family life".