The Iron Lady came face to face with her silkier side yesterday when Baroness Thatcher attended the unveiling of a new portrait.

The former Prime Minister hailed the "striking" work by 28-year-old Benjamin Shine which is made from chiffon ribbons threaded on to an iron base.

Lady Thatcher, dressed in a pale blue suit, told the award-winning artist he had done "a wonderful job".

"I think it's very striking, it's remarkable," she said at the unveiling ceremony in London's Dorchester Hotel.

However, she added: "I'm not as fierce as that."

It was a rare public appearance for the frail 80-year-old but one which delighted the young artist.

He spent 250 hours creating the work which he first conceived after meeting her at an exhibition in 2003.

It was encountering the "human side" of the politician that inspired him to seek permission for the portrait and his choice of materials.

Although the ex-Prime Minister sat for early sketches, the finished piece - which measures 4ft x 5ft - was mainly based on photographs.

Composed rather like a dot-to-dot puzzle, it is the second such portrait Mr Shine has created of public figures who have inspired him. The first was of Sir Edmund Hillary, conqueror of Everest inn 1953.