Lowe began the first series of The West Wing as the lead actor

Lowe - who played White House Deputy Communications Director Sam Seaborn - left the programme in March 2003, amid rumours of a dispute over his salary.

He will return with other former stars of the Emmy-winning drama, which is set to end after seven series.

NBC announced in January they were axing the drama because of a fall in audience numbers.

Unprecedented success

The show's finale follows the death of actor John Spencer, who played Leo McGarry, in December at the age of 58.

Set in the West Wing of the White House, the series follows fictional Democratic president Josiah "Jed" Bartlet, played by Hollywood veteran Martin Sheen, and his administration.

Rumours of the demise of the show began in 2005

It has won an unprecedented 24 Emmy awards and two Golden Globes since it began in 1999.

Lowe was nominated for an Emmy for his performance in 2001.

Other former stars returning include Mary-Louise Parker, who will return as women's-rights advocate Amy Gardner, CSI: Miami's Emily Proctor, Marlee Matlin, Gary Cole, Tim Matheson, Timothy Busfield and Annabeth Gish.

They will appear on one or more of the final episodes, but not necessarily the finale, which will air in the US on 14 May 2006.