Sir Paul McCartney finally drew a line under his grief for tragic wife Linda when he announced last night that he and girlfriend Heather Mills are engaged and will marry "some time next year".

The former Beatles star is thought to have gone down on one knee to make his proposal to the North-East model and landmine campaigner.

The pair became engaged during a short break in the Lake District with the millionaire pop idol popping the question on Monday.

A statement on behalf of the couple said: "Paul McCartney and Heather Mills are pleased to announce their engagement.

"The couple are looking forward to being married some time next year.

"Paul and Heather would like to thank their relatives and friends for all the great support they have shown them since they met two years ago."

The couple met at an awards ceremony and saw each other as friends before they began dating.

Sir Paul's spokesman said: "He bought the ring in India earlier in the year. It is sapphire and diamond, but predominantly sapphire."

The couple had holidayed near the pink city of Jaipur in Rajasthan.

Asked whether the pop legend's proposal was on one knee, he said: "I think it was."

The spokesman added: "They are both delighted, as are the kids and as is everyone."

Sir Paul lost his first wife Linda in April 1998 when she lost a long battle against cancer. He spent months mourning but towards the tail end of 1999 he said he had begun to emerge from the grief.

The former Beatle and Linda were married for 29 years and were always at each other's sides,

Sir Paul, 59, said about the loss of Linda: "I lost my girlfriend, lover, wife and the mother of my children."

There had been speculation that Sir Paul and Heather would tie the knot but he has dodged the question when asked by reporters over the past few months.

Heather, 33, has also been married once before, to Alfie Karmal, although it was short-lived.

She and Sir Paul came clean that they were "an item" in March 2000.

Sir Paul was a huge heart-throb during the band's domination of the pop world throughout the Sixties, but has been linked with only three women seriously.

He fell in love with Jane Asher in 1963, they later moved in together and she was the inspiration for many of his songs such as And I Love Her and We Can Work It Out.

They decided to get married and became engaged on New Year's Day 1968, but split after he had an affair.

He met Linda that year and they married when she was four months pregnant.

Heather, originally from Washington, Tyne and Wear, had been a swimwear model until she lost her leg below her knee when a police motorcycle hit her as she crossed a road in London.

She battled back to health and has devoted much of her time to helping others with similar disabilities and promoting fundraising efforts for landmine victims.

Heather has also been a TV presenter and has tried her hand at acting.

Her marriage to Karmal in 1989 was shortlived, ended by her relationship with a Slovenian skiing instructor.

In her autobiography, Out on a Limb, she wrote about how she suffered the tragedy of two ectopic pregnancies.

In 1999, Mills had been due to marry documentary cameraman Chris Terrill, but two weeks before the ceremony, the wedding was called off.

Sir Paul is due to release a new album in November and a series of impromptu gigs is expected in the coming months.

Last night, he joked with the media outside his home in St Johns Wood, London, and accused them of having married him off months ago.

Asked how he proposed to his fiancee, Sir Paul, who looked relaxed and wore a white shirt and casual trousers, said: "That's private, that's just for me."

He then went back inside to have a quiet dinner with his future wife.

More music news is available from Revolution