Neil MacGregor, the former head of the National Gallery, takes up his new position as director of the British Museum on Thursday.

He is replacing the current director, Robert Anderson.

Mr MacGregor joined the National Gallery in 1987 and oversaw the completion of the Sainsbury Wing and the refurbishment of the whole main display.

The trustees of the British Museum gained the formal approval of Prime Minister Tony Blair before announcing the appointment.

Neil MacGregor made the BBC series Seeing Salvation

Mr MacGregor, 55, was educated at Oxford and in Paris and Edinburgh, and has written a number of books on architecture and art history.

In 2000 he presented the major BBC series Seeing Salvation, which, over four programmes, examined images of Christ in western art.

"I am very honoured to be given the chance to lead The British Museum, one of the great museums of the world," said Mr MacGregor.

"After 15 happy years at the National Gallery, I shall greatly miss the colleagues and the pictures at Trafalgar Square."

The chairman of trustees at the British Museum, Graham Greene, said Neil MacGregor had been "outstandingly successful" at the National Gallery.

About 5.5 million people visit the museum annually

He was confident Mr McGregor would lead the British Museum with "equal distinction" in the run-up to its 250th anniversary, in 2003, and beyond, he added.

Charles Saumarez Smith, formerly of the National Portrait Gallery, is taking over at the National Gallery.