FILE - The 'Iron Lady' MARGARET THATCHER has died following a suspected stroke at the age of 87 her spokesman said Monday. The Conservative Party leader was the first and only female British Prime Minister and the the longest-serving Prime Minister of the United Kingdom of the 20th century, from 1979-1990. PHOTO: Jan. 5, 1980 - London, England, United Kingdom - MARGARET THATCHER speaking during a conference. (Credit Image: © KEYSTONE Pictures USA/ZUMAPRESS.com)