House of Lords leader Baroness Amos has been nominated by the UK to head up the United Nations Development Programme.
Lady Amos was the first black woman leader of the Lords
If successful, she will take over from fellow Briton Mark Malloch Brown, who has been appointed chief of staff to UN Secretary General Kofi Annan.
The job Lady Amos has been put forward for is one of the UN's most senior.
A Downing Street spokesman confirmed the Labour peer has been nominated by Tony Blair and said she was considered "a very strong candidate" for the job.
"Valerie Amos has an excellent blend of political, diplomatic and leadership skills and an impressive track record in government," the spokesman said.
"From her time as Secretary of State for International Development, she has great experience of development issues and is well-known and respected throughout the international community."
Baroness Amos, 50, was created a life peer in August 1997. Her rapid rise through government ranks began a year later when she was appointed a Government whip in the House of Lords.
She became a foreign office minister in 2001 and international development secretary in 2003.
She was appointed Lords leader following the sudden death of Lord Williams of Mostyn in October 2003.
She was born in Guyana in March 1954, the eldest of three.
The family moved to Kent when she was 11 because of her teacher father's concern for their future education.
The head of the development programme would be expected to champion the UN's Millennium Development goals to halve extreme poverty by 2015.
Jan Pronk, the former Dutch development minister, is also being touted for nomination to the New York-based role.
A decision is expected to be announced by the end of March.