The US supreme court justice is to step down, US media have reported.

David Souter is expected to leave his position at the end of the current court session in June.

After 19 years in the post, his departure will allow Barack Obama, the US president, to name his first judge for the country's highest court.

Observers suggest that Obama is likely to pick a woman for the post.

The Washington Post newspaper reported on Thursday that Joseph Biden, the vice-president, had been asked to draw up a list of nominees.

Contenders could include Elena Kagan, who now represents the government before the supreme court.

Speculation that Souter, 69, was planning to retire started after he failed to appoint clerks for the court term that starts in October.

Souter is seen as having Republican roots and as disliking Washington. He once described his situation as "the world's best job in the world's worst city".

An unmarried liberal intellectual, he upheld abortion rights in 1992 and voted to support the government's right to seize property to foster economic development.

Souter nor the White House have yet commented on his possible departure.