The mood is unlikely to be light-hearted at Buckingham Palace as the austere Mr Hu comes to stay. He is devoid of the theatricality of his predecessor Jiang Zemin. On the last Chinese state visit, six years ago, Mr Jiang unexpectedly grabbed the microphone for a karaoke session.

Jiang belted out a 1930s Broadway hit, "Our Hearts Were Young and Gay". An embarrassed John Prescott responded in kind with "For he's a jolly good fellow", to the outrage of those concerned with China's human rights record.

Tony Blair said the state visit would be an opportunity to discuss Britain's trade with China and global issues including climate change and international security. Aides say Mr Blair has to forge a close relationship with such a large economic and political power.

Mr Blair said: "We will discuss the economic relations between our two countries, which are growing. We will discuss, of course, the current security preoccupations in the world and how we co-operate better on the Security Council. We will discuss issues to do with climate change, where the Chinese have taken part very constructively in the G8-plus-five dialogue last week."

But Stephen Bowen, of Amnesty International, said: "It is imperative that Tony Blair raises human rights issues during this visit. China still massively restricts freedom of expression and information, still executes more people than the rest of the world put together and still harasses and detains people who stand up for human rights."

A spokeswoman for the Liberal Democrat leader Charles Kennedy said he would raise "strongly" concerns about China's human rights record during his meeting.

The Free Tibet campaign will hold demonstrations in London today and tomorrow in protest at the visit.

Downing Street said that Mr Blair had discussed human rights during his visit to Beijing earlier this year, insisting that the Government regularly raised the issue with the Chinese. "We will raise things as part of a private dialogue," a spokesman said.

As with President Hu's recent visit to the US and Canada, the protesters are not expected to disturb the businesslike progress of the trip. During the last Chinese state visit the Metropolitan Police took extensive measures to ensure that Mr Jiang did not see any protesters.

China's prominence on the world stage - as a major consumer of raw materials, a polluter with emissions of CO2 soon to rival America's and an exporter of cheap manufactured goods ensure that its concerns are carefully listened to.

World leaders have been rolling out the red carpet for the man running the most turbo-charged economy on earth.

As head of the Communist Party, state president and commander-in-chief of the army, President Hu's grip on the levers of power rivals Mao Zedong's at its zenith. If China's economic growth continues at the same pace, it is expected to pass its great rival Japan and become the second largest economy in the world after the US by 2020.

China's economic boom is paying for a rapid growth in the country's military - now the third or fourth largest in the world. And one of President Hu's key objectives in visiting Britain - which holds the EU presidency - is to have the ban on arms exports lifted. Imposed after the bloody crackdown by the Chinese military in Tiananmen Square, the ban is a major irritant for China - which sees it as an effort by the US to keep its military in check.

Since becoming President in 2003 President Hu travelled across Asia, South America and Africa, as well as several European countries.

China's relationship with the European Union is still uncertain with both side circling round each other. This summer a row blew up over textile exports to Europe and the arms embargo continues to rankle.

Ahead of the visit, China's Foreign Minister Li Zhaoxing described the ban on arms sales as "political discrimination". He called it "a legacy of the Cold War. It is poorly founded, useless and can only be harmful. This should have been scrapped a long time ago". Earlier in the year, the Foreign Secretary Jack Straw made the prediction that that the embargo would go within six months, to be replaced by a strict code of conduct which would in fact still restrict arms sales. The US remains implacably hostile however.

In the meantime China passed a law permitting military action against Taiwan should it move towards a declaration of independence. This caused the EU to slam on the brakes. Asked about the embargo, a Foreign Office official would only say that Britain is "moving towards lifting the embargo and continues to discuss it within the EU".