The National Gallery is asking the public to help raise the last £2 million it needs to buy a painting of “outstanding importance for the national heritage”.

It wants The Finding Of Moses by Orazio Gentileschi (early 1630s) to be able to stay on free public display at the art museum in Trafalgar Square, London.

The painting is one of just a handful of works painted during Gentileschi’s 12-year residence in London at the court of King Charles I.

The Finding Of Moses
The Finding Of Moses (National Gallery/PA)

It was commissioned to celebrate the birth of the future Charles II and intended to hang in the Queen’s House at Greenwich.

The Finding Of Moses has been on long-term loan to the National Gallery from a private collection for almost 20 years.

The full cost of the artwork is £22 million but the net cost to the gallery is £19,471,340 by a private treaty sale arranged through Sotheby’s and Pyms Gallery.

As a charity, the National Gallery depends on public generosity.

The organisation said it is “enormously grateful for exceptional grants of £2.5 million from the National Heritage Memorial Fund and £1 million from Art Fund”.

A total of £8.5 million is coming from The American Friends of the National Gallery, London, with £5 million from The National Gallery Trust.

A further £500,000 of gifts left in wills to the National Gallery is also being used towards the acquisition.

This leaves £2 million left to raise.

Stephen Deuchar, director of Art Fund, said: “The Finding Of Moses is one of the National Gallery’s most precious long-term loans and its prospective sale provides the gallery with an important opportunity.

“My trustees have committed £1 million, one of our largest grants to date, towards the acquisition and we hope that other funders and members of the public will feel as strongly about playing a part – big or small – in saving this masterpiece for everyone to enjoy in the national collection.”

National Gallery director Dr Gabriele Finaldi said: “If the National Gallery succeeds in buying the painting, it will be here for everyone to enjoy for generations to come.

“The Finding Of Moses will have found its definitive audience among the nation’s pictures.”

For information visit www.nationalgallery.org.uk/saveorazio