By Greg Barrow BBC UN correspondent

A grassroots campaign in the United States has raised more than $1m to support the UN's Population Fund.

The agency has been facing a cash shortfall following a decision last year by the US Government to withdraw financial support.

China condemned the decision to cut funds

The Bush administration froze $34m in funding, citing allegations that the UNFPA was involved in forced abortions in China - a charge that has been consistently denied by the organisation.

The campaign aims to generate a sum of money to bridge the gap caused by the freeze in funding by Washington.

It was started by two American women, Lois Abraham and Jane Roberts, who say they were angered by their government's decision to freeze the funds for a UN agency that works around the world to make childbirth safer, and to limit the spread of HIV.

Their idea is simple - to persuade 34 million Americans to contribute a dollar each to the UNFPA and thereby cover the shortfall in funding.

In less than a year, they have raised $1m in contributions from around 100,000 people.

Ms Roberts said the response demonstrated the strength of feeling about this issue in the United States:

"Even though our government has chosen not to participate in the work of UNFPA, we the people are participating. And that is a wonderful message to send to the world."

The decision by the US Government to withdraw funding followed allegations from conservative religious groups in America that the UNFPA was supporting forced abortions in China.

Subsequent independent investigations found no evidence to support this, but still no decision has been taken to review the funding freeze.