PRIME Minister Kevin Rudd has set the Christian lobby, a key Labor powerbroker and a crucial balance-of-power Senator against him over Australia's move to scrap a 13-year-old ban on foreign aid being used to fund safer abortions for women in poor nations.

But the historic shift was lauded by a wide array of aid agencies, women's groups, family planning experts and many cross-party federal politicians, who said it would save the lives of thousands of women who would otherwise die in botched backyard operations.

The Prime Minister was targeted by his Christian base after revealing that he backed but did not personally support the decision by Foreign Minister Stephen Smith to axe the ban - two months after US President Barack Obama overturned a similar ban in his country.

Mr Rudd told a meeting of Labor MPs he had "long-standing conservative views" on the issue, but said a clear majority of Labor MPs backed a change.

The Australian Christian Lobby, which gave him a platform to reach 100,000 Christians by TV before the last election, threatened to campaign against him at the next election.