Kent: Directed Cate Blanchett in David Hare's Plenty

But the pair, who were responsible for attracting Kevin Spacey, Juliette Binoche and Cate Blanchett to their stages in north London, have denied the rumours.

"There is no hidden agenda," said Mr McDiarmid.

"To have created, along with many others a theatre of vision and commitment has been entirely rewarding, but we believe now is the time to go."

Vibrant

Mr Kent and Mr McDiarmid were both originally actors who met at the Glasgow Citizens' Theatre and will continue their directorship at the Almeida until Summer 2002.

They are considered two of the most successful and influential directors at work in this country, creating vibrant theatre since they started in 1990.

The Almeida was a 300-seat music hall theatre in north London, which did not generate its own productions until Mr Kent and Mr McDiarmid came along.

The Almeida has now had 15 world premi�res, including works by Edward Albee, Neil LaBute, Harold Pinter, David Hare and Phyllis Nagy.

McDiarmid: Played Emperor Palpatine in Return of the Jedi

Under their stewardship the theatre has won more than 45 theatre awards, including a Laurence Olivier Award and an Evening Standard Award, both for Outstanding Achievement.

Mr Kent, who is now exclusively a director, worked to great acclaim at the National, particularly for a production of Mother Courage starring Diana Rigg.

His most recent production, David Hare's new adaptation of Chekhov's Platonov, is currently playing at the Almeida at King's Cross.

Upcoming projects include a production of Dancing at Lughnasa playwright Brian Friel's Faith Healer followed by King Lear in January 2002.

Mr McDiarmid has appeared in such films as Return of the Jedi and The Phantom Menace and is about to tread the boards again, taking the role of Freddy in Faith Healer.

Rachel Weisz starred in Neil LaBute's The Shape of Things

The Almeida's current home is a disused bus depot in Kings Cross while the original theatre in Islington is being refurbished.

Almeida chairman Garry Hart paid tribute to the achievements of Mr Kent and Mr McDiarmid and said he hoped to find a worthy successor.

"The board is determined that the re-opening of the refurbished Almeida should be marked by the choice of a successor who will be able to bring to their work the same artistic distinction, creativity and vitality," he said.

The Almeida will return to Islington in winter 2002.

The post of artistic director for the Almeida will be advertised next month.