A man in a hat smoking a pipe, a shirtless male torso and a floating eye are among the doodles reportedly scribbled by US president Ronald Reagan during a high level international summit in 1981.

The sketches are among Margaret Thatcher's private papers being released by archivists who have catalogued the former prime minister's files.

Thatcher is thought to have swiped the drawings during a break in proceedings at a conference in Ottowa, Canada, in 1981.

Records show that Thatcher and Reagan were joined at the "group of seven" (G7) summit by Canadian Prime Minister Pierre Trudeau, French President François Mitterrand, West German Chancellor Helmut Schmidt, Italian President Giovanni Spadolini and Japanese Prime Minister Zenko Suzuki.

It is not clear if the Republican president was drawing any of those present, as he left no indication whose faces, or whose body, he was trying to capture.

However Thatcher wrote "Ronald Reagan's 'doodling' at the Ottawa Conference" in the bottom right hand corner of the page in order to remind her of its origin.

Reagan, who served as US president between 1981 and 1989, became a close ally of Tatcher as America and Britain faced down the Soviet Union in the final decade of the Cold War.

Chris Collins, a historian who works for the private-funded Margaret Thatcher Foundation, said he recalled the former Conservative leader talking about Mr Reagan's doodling.

"She was sitting next to him," said Collins. "She had seen him doing it during the meeting. He just left it on his desk. He thought it was of no value whatsoever and left. She thought it was rather fun and picked it up."

Reagan is not the first US president to scribble on paper during a high-level international summit. In president Geroge W Bush was caught on camera writing a note to secretary of state Condelezza Rice to let her know he needed a toilet break.