Britain will consider withholding aid from countries that do not recognise gay rights, Prime Minister David Cameron said on Sunday, after Commonwealth leaders failed to adopt reforms on the issue.

"Britain is now one of the premier aid givers in the world. We want to see countries that receive our aid adhering to proper human rights, and that includes how people treat gay and lesbian people," Cameron told the BBC.

He added: "British aid should have more strings attached, in terms of do you persecute people for their faith or their Christianity, or do you persecute people for their sexuality. We don't think that's acceptable."

Cameron was speaking at the end of a Commonwealth leaders' summit in Perth, western Australia, which failed to adopt a recommendation to call for an end to homophobic laws in 41 member nations.

He insisted the issue of gay rights had been discussed at the summit and he had personally raised it with "a number of the African countries that I've been speaking with," although he would not say which ones.

"We've been raising the issue consistently, we've been raising it here at this Commonwealth heads of government (summit)," he said.

However, Cameron said change would not happen overnight, saying: "They are in a different place from us on this issue. ... I think these countries are all on a journey and it's up to us to try and help them along on that journey."