London's Tate Modern gallery plans to open all night to accommodate massive demand for the Matisse Picasso show before it closes.

More than 250,000 have already been to see Matisse Picasso and a further 150,000 are expected before its close next month.

Opening hours will be extended for a month, and the final weekend of 17 and 18 August will see the venue open for a marathon 36-hour period to get all the art fans through the doors.

It will be one of the five most popular exhibitions in the history of Tate when it closes

Tate Modern

The show has been a huge hit already with visitors having to buy tickets for restricted time slots in an effort to prevent overcrowding.

It traces the changing styles of both artists and the links between their work.

Matisse Picasso will open each day from July 19 until 2200 BST, then on the final weekend Tate Modern will open at 1000 BST on 17 August and finally close its doors at 2200 BST the following evening.

A spokeswoman for the gallery said there had been an "extraordinary number" of visitors.

"It will be one of the five most popular exhibitions in the history of Tate when it closes," she said.

Picasso's work is loved by millions

"It is anticipated that some 400,000 visitors in total will see the show."

During the overnight session broadcaster and musician George Melly will give a tour, as will Tim Marlow who presented Channel 5's recent programmes about the Tate.

Tate bosses will also open an absinthe bar serving the notorious green drink which fuelled many of the wilder visions of great artists.

Matisse Picasso opened on 11 May, the Tate Modern's second birthday.