A �1m 17th Century portrait has gone on display at London's Tate Britain after a fundraising campaign to keep it from going abroad.

The Portrait of Sir William Killigrew by Sir Anthony van Dyck was saved for the nation by donations from art benefactor Christopher Ondaatje and arts foundations - as well as a break from the Inland Revenue.

This is an extremely significant work

Sir Nicholas Serota, Tate Gallery

More modern works, by Stanley Spencer and Pierre Bonnard, have also been kept for display in the UK thanks to the new tax regime.

Van Dyck's work was secured by a donation of �100,000 given by financier and philanthropist Christopher Ondaatje - who helped fund recent renovations at the National Portrait Gallery - along with �100,000 from The Patrons of British Art and �50,000 from the National Art Collections Fund.

The government helped through an arrangement which allows works of art to be accepted in lieu of tax, in this case assessed at �250,000.

The Tate gallery also contributed, though the exact price of the painting - which is thought to be worth �1m - has not been disclosed.

Key figure

The portrait by van Dyck (1599-1641) is said to have been in private ownership since it was created, and was last displayed publicly 20 years ago at the National Portrait Gallery's exhibition of the painter's works.

Van Dyck, born in present-day Belgium, was a pupil of Sir Peter Paul Rubens and a key figure in the development of British portrait painting, influencing Sir Joshua Reynolds and Thomas Gainsborough, among others.

He painted for the court of Charles I from 1632 after many years in Venice where he studied the works of Titian.

His study of Sir William Killigrew is a thoughtful three-quarter length portrait from the later part of his career.

Tate director Sir Nicholas Serota described it as "an extremely significant work".

Other paintings which have been saved for the nation include Le Repas by Pierre Bonnard, which will go to the Fitzwilliam Museum in Cambridge, and Stanley Spencer's View from Cookham Bridge, inspired by a view close to his Berkshire home.

A collection of 20th century art made up of many works by avant garde artist John Piper, a sculpture by Alexander Calder and a painting by Jean Hilion will go to the Tate, the Fitzwilliam Museum, Buckingham Museum and the Pallant House Gallery in Chichester.