World leaders paid tribute to former British prime minister Margaret Thatcher after her death was announced Monday.

Chinese Premier Li Keqiang on Tuesday extended condolences to British Prime Minister David Cameron, the Xinhua News Agency reported.

"Thatcher was a prominent stateswoman who made great contributions to the development of Sino-British relations, including the peaceful settlement of the Hong Kong issue," said foreign ministry spokesman Hong Lei.

Hong Kong Chief Executive Leung Chun-ying also extended his deepest condolences on Tuesday to the people of Britain on behalf of the Hong Kong Special Administrative Region Government and the people of Hong Kong.

Downing Street is flying flags at half mast to honor Thatcher. The BBC quoted Cameron as saying that "she didn't just lead our country, she saved our country, and I believe she'll go down as the greatest British peacetime prime minister."

In a statement, US President Barack Obama said, "The world has lost one of the great champions of freedom and liberty, and America has lost a true friend." He praised Thatcher as an example to American women seeking to break the gender barrier, and also hailed her as a loyal political ally of the US during the Cold War.

Russian President Vladimir Putin expressed his condolences to Cameron Tuesday. Russia's Itar-Tass reported that Putin said people in Russia will remember Thatcher as a person who made a significant contribution to the development of dialogue and mutually advantageous relations between the two countries.

The BBC reported that Mikhail Gorbachev, the former leader of the Soviet Union, said he and Thatcher were able to reach mutual understanding, and this contributed to changes in the atmosphere between the USSR and the West and to the end of the Cold War.

German Chancellor Angela Merkel described Thatcher as "one of the greatest leaders in world politics of her time." Merkel said she would never forget her contribution to overcoming Europe's partition and the end of the Cold War.

Qian Chengdan, a professor of history with Peking University and president of the China British History Association, told the Global Times that Thatcher made a swift and wise political choice in returning Hong Kong to China when she was in power.

"Hong Kong was the last major territory under British colonial rule when she came into power. Most of Britain's colonies had then regained independence through war. Under those circumstances, keeping Hong Kong was against Britain's interests, not to mention China's determination to take it back," said Qian.

Qian said the Hong Kong issue was then the major barrier to the development of the Sino-British relationship and Thatcher made a practical decision in handing over Hong Kong.

"Thatcher returned Hong Kong safely to China without a referendum or political unrest and also ensured Hong Kong's position as China's territory with both sovereignty and the right to govern. This showed Chinese leaders' and Thatcher's political wisdom," said Qian.\

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