British Prime Minister David Cameron cut short a European tour he was on to return to the United Kingdom and led tributes to Margaret Thatcher, who died at the age of 87 on Monday.

Lady Thatcher, the former British prime minister, suffered a stroke, her spokesperson said, and her funeral will be at St. Paul's Cathedral with full military honors followed by a private cremation.

Thatcher served from 1975 to 1990 as leader of the Conservative Party. She was called the "Iron Lady" for her political toughness in a field led mostly by men, according to CNN, and she was the first and only female British prime minister. She left the public life behind after suffering a stroke in 2002 and had several strokes after that. She was hospitalized in December 2012 after having surgery to remove a growth in her bladder, according to the news report.

Thatcher was born in October of 1925 in the eastern England town of Grantham. She was a grocer's daughter, studied chemistry at Oxford and gave her first political speech at the age of 20, according to her official biography. She was elected leader of the Conservative Party in 1975. Her British leadership and journey to the position inspired the 2011 film The Iron Lady, in which actress Meryl Streep played Lady Thatcher.

Cameron said in a statement, "It was with great sadness that I learned of the death of Lady Thatcher. We have lost a great leader, a great prime minister and a great Briton."

He heard news of Thatcher's passing while in Madrid meeting the Spanish prime minister, according to Guardian. The Queen was also saddened by the news of Thatcher's death. Buckingham Palace released the following statement:

"The Queen was sad to hear the news of the death of Baroness Thatcher. Her Majesty will be sending a private message of sympathy to the family."

Former prime minister Tony Blair called Thatcher "a towering political figure."

"Very few leaders get to change not only the political landscape of their country but of the world. Margaret was such a leader," he said. "Her global impact was vast. And some of the changes she made in Britain were, in certain respects at least, retained by the 1997 Labour government, and came to be implemented by governments around the world."

Thatcher's husband, Denis Thatcher, died in June 2003. Together they had twins Mark and Carol in 1953.