David Hockney donated his largest ever painting to the Tate today and called on the Government to make it easier for artists to make gifts of their work.

Depicting a Yorkshire landscape in spring, Bigger Trees Near Warter 2007 measures 15x40ft and was painted on 50 separate pieces of canvas.

The painting, which would sell for millions on the open market, spanned a whole wall at the Royal Academy when it was the star of Summer Exhibition show last year.

The largest piece of work ever given to the Tate will go on display at Tate Britain in autumn next year, in whole as well as in parts.

Bradford-born Hockney, who has seven paintings in the Tate Collection, first became mesmerised by the landscape around where he grew up four years ago and is now leasing a warehouse in the area.

The artist, 70, said of his gift: "The Tate asked me two years ago about giving things.

"I thought 'If I'm going to give something to the Tate I want to give them something really good. It's going to be here for a while. I don't want to give things I'm not too proud of'."

Hockney, who is also planning to give another, older Yorkshire landscape painting, said: "I thought this was a good painting because it's of England...It seems like a good thing to do."

The artist, who has lived in LA - the scene of many of his most famous paintings - for almost 30 years, added: "In America, people who donate works to American museums get tax reductions.

"So people have been very generous, that's why they have got very, very good collections.

"Perhaps it would be better to provide something like that (in the UK).

"In America there's a very worked out system. In LA, since I have been there, some four new museums have been built."

Editor's choice

• The 100 Best Films of the Decade
• 70 facts you didn't know about Marvel
• The 50 Biggest Movies Of 2010