The premiers of Britain and China on Tuesday oversaw the signing of deals worth more than one billion dollars, as visiting Prime Minister David Cameron looks to boost London's fragile economy.

Cameron -- plus 43 bosses from major British companies and four ministers in Britain's largest-ever delegation to China -- says he wants to take his country's ties with the world's second-biggest economy "to a new level".

But the British premier, on his first official visit to China, was under high pressure to challenge Chinese leaders on human rights issues -- a challenge he insisted he was up to and would fulfil.

At a signing ceremony attended by the premiers after their talks, Rolls-Royce and China Eastern Airlines inked a 1.2-billion-dollar deal under which the British group will provide jet engines to power 16 Airbus A330 jets.

Two education cooperation agreements were also signed.

Cameron said in a column for the Wall Street Journal that he expected to see "new contracts worth billions of dollars" signed during his two days in Beijing, which come ahead of the Group of 20 summit in Seoul starting Thursday.

His longer-term target is to double the level of trade in goods and services between Britain and China by 2015, from last year's 51.8 billion dollars.

Cameron's efforts to build business ties with Beijing however risked being eclipsed by increasing calls for him to issue a stern rebuke to Premier Wen Jiabao and President Hu Jintao on their human rights record.

Cameron is the first Western leader to visit China since jailed dissident Liu Xiaobo was awarded the Nobel Peace Prize on October 8 -- an honour hailed in the West but decried by Beijing as tantamount to "encouraging crime".

Liu, 54, was jailed in December for 11 years on subversion charges after co-authoring Charter 08, a bold petition calling for democratic reform in one-party China that has been widely circulated online and signed by thousands.

When asked if he would press China's Communist leaders on rights issues, Cameron said such questions were part of London's wide-ranging dialogue with Beijing.

"That is how it should be. Of course we shouldn't be lecturing and hectoring but it is right we have a dialogue on these things," he told British broadcasters.

Asked if he feared jeopardising trade deals by being forthright on human rights, Cameron replied: "I don't think that's the way these relationships should work."

British officials declined to specify which particular cases Cameron wanted to discuss with China's leaders.

On the eve of Cameron's visit, Chinese artist Ai Weiwei, an outspoken government critic who was placed under house arrest at the weekend, said Western leaders on trade trips to China "must insist on human rights issues".

Countries including Britain have said they will not heed a Chinese call for Western diplomats to steer clear of the Nobel Peace Prize award ceremony in December.

On Tuesday, the lawyer who heads the firm that represents Liu, Mo Shaoping, told AFP that he was prevented from boarding a flight out of China, saying the Nobel connection was "definitely" behind the decision.

Cameron remained keen to emphasise the potential gains for Britain, not the sticking points, saying the deals signed in Beijing would help "take Britain's relationship with China to a new level".

"I'm proud that we have brought a really big trade delegation here, bigger even than the one we took to India," he told Sky News.

Cameron's coalition government, which took power in May, is searching for new sources of economic growth after unveiling the deepest public sector spending cuts in decades last month.

His ministers are battling to tackle a record deficit of 154.7 billion pounds (249.3 billion dollars).

Earlier deals signed include a 45-million-pound, five-year agreement for British companies to export breeding pigs to China and the construction of 50 new English-language schools in China by Britain's Pearson.

In a bid to highlight the opportunities for British companies in China, Cameron's first visit was to a supermarket run by Tesco, the world's third largest retailer, in south Beijing.

The British premier will meet Hu and attend a business summit on Wednesday before heading to South Korea.