Ex-UK PM Thatcher leaves hospital

LONDON, England (CNN) -- Former British Prime Minister Margaret Thatcher walked out of a London hospital Saturday morning where she spent the night after feeling "unwell" during a dinner at the House of Lords.

Thatcher, 82, was admitted to St. Thomas's Hospital near Parliament for tests Friday night, the former PM's spokeswoman Gillian Penrose said.

Thatcher appeared alert and strong as she walked from the hospital and stepped into a waiting car. She paused briefly to wave to people gathered to watch her departure.

Nicknamed the "Iron Lady" by the Soviet press after a 1976 speech criticizing communism, Thatcher enjoyed a close working relationship with U.S. President Ronald Reagan, with whom she shared similar conservative views.

Although her doctors advised against public speaking, a frail Thatcher attended Reagan's 2004 funeral, saying in a pre-recorded video that Reagan was "a great president, a great American, and a great man."

"And I have lost a dear friend," she said.

Thatcher was elected head of the Conservative Party in 1975 and took office as prime minister when the Conservatives won control of the government in 1979. She won re-election in 1983 and 1987, but was forced to resign three years later during an internal leadership struggle after she introduced a poll tax levied on community residents rather than property.

The unpopular tax led to rioting in the streets.

During her time as prime minister, she emphasized the rights of the individual versus that of the state, moral absolutism and nationalism.

In her first term, Thatcher reduced or eliminated many government subsidies to business, a move that lead to a sharp rise in unemployment. By 1986, unemployment had reached 3 million.

She retired from public life following a stroke in 2002 and suffered several smaller strokes after that. She was named Baroness Thatcher of Kesteven after leaving office.

Thatcher was Britain's first and only female prime minister and the first 20th century British leader to win three terms. E-mail to a friend

CNN's Daniela Berretta in London contributed to this report.

Copyright 2008 CNN. All rights reserved.This material may not be published, broadcast, rewritten, or redistributed. Associated Press contributed to this report.

All About Margaret Thatcher