His appointment reflects the importance the government places on managing relations with the US.

Mr Li, 62, is known for his pugnacious style - uncommon for a diplomat - in confronting China's critics.

During his tenure as ambassador to Washington from 1998 to 2001, Sino-US relations went through a turbulent period. Then president Bill Clinton's visit to China put bilateral ties back on track, but allegations of Chinese espionage, human rights abuses and illegal political contributions periodically threatened to derail the relationship.

Ties reached a low in 1999 when Nato aircraft bombed the Chinese embassy in Belgrade. Mr Li went on US television to tell the American people that such a brutal incident could not have been a 'casual mistake' and demanded an investigation and an apology.

In February 2000, Senator Jesse Helms, chairman of the US Senate Foreign Relations, wrote to the Washington Times complaining about remarks by a diplomat at the Chinese embassy who called the US Congress 'a reckless and irresponsible body' for voting on a bill to arm Taiwan with more weapons.

Standing by his colleague, Mr Li wrote back that mainland opposition to the bill was justified and lamented the fact that some US congressmen, including Senator Helms, did not have 'adequate knowledge of the origin of the Taiwan question and the evolution of China-US relations'.

Mr Li's detractors got even with him after he failed to show up before the American Congress, where he had agreed to testify on China's human rights record.

A year later when an American surveillance plane and a Chinese fighter jet collided over the South China Sea, Mr Li was again put in the difficult situation of having to condemn the incident without doing serious damage to relations with the US.

A native of Shandong, Mr Li is a graduate of Peking University. After joining the Ministry of Foreign Affairs, his overseas assignment took him to Kenya and Lesotho. Back in Beijing, he served as the ministry's spokesman, an experience that polished his media skills.

Sun Zhe, professor of American studies at Fudan University, said Mr Li was the first Chinese diplomat to speak to mainstream media and directly interact with the American people.

'Even though some may not agree with him, the American public admire people with character,' he said.

As foreign minister, Mr Li would likely reach out beyond his counterparts in the State Department to the Congress and various interest groups active in American politics, Professor Sun said.

'Minister Li is a veteran diplomat who has a clear idea of our country's interest,' said Cheng Zhengming, a deputy from Gansu. 'We are fortunate to have him to manage the foreign relations in such a volatile time.'

Meanwhile, Mr Tang, 65, was made a state councillor and will oversee affairs with foreign countries as well as Hong Kong, Macau and Taiwan.

A mild-mannered career diplomat, Mr Tang had been the ministry's top Japan specialist. He stumbled in his first year as foreign minister in 1998 when he was held responsible for a disappointing state visit by former president Jiang Zemin to Tokyo. The Japanese government did not give a pledge that China sought on the Taiwan issue.

Mr Tang will set foreign policy direction and Mr Li will handle day-to-day affairs.