MANCHESTER, England/BEIJING (Reuters) - Chinese President Xi Jinping has told Britain he wants to see a united European Union, in his most direct comments on Britain's relationship with Europe before the country's EU membership referendum.
Xi told Prime Minister David Cameron Britain was an "important member of the EU" before ending his four-day trip to Britain which sealed multi-billion dollar deals but drew criticism from human rights campaigners.
It was a rare mention of another country's planned vote by China, which does not like to interfere in internal affairs, and was quickly played down by a Cameron aide, who said the European Union "wasn't a huge part of their discussion".
Officials, instead, are keen to steer attention to the large-scale investment Britain has secured from China. Xi went to the northern city of Manchester on Friday, where the government hopes to encourage investment to spur the creation of a 'northern powerhouse' to challenge London's dominance.
China's foreign ministry paraphrased Xi as saying in a statement: "China hopes to see a prosperous Europe and a united EU, and hopes Britain, as an important member of the EU, can play an even more positive and constructive role in promoting the deepening development of China-EU ties."
Cameron is seeking to renegotiate Britain's relationship with the EU, which it joined in 1973, before holding a referendum on membership which he says will take place before the end of 2017.
But Beijing has been worried about the implications of free trade-supporting Britain leaving the EU, and of any weakening of a grouping which it views as a vital counterbalance to the United States, diplomats say.
Opinion polls have showed a narrowing of support among British voters for staying in the EU and one on Thursday showed a sharp slump in backing for its membership amid concerns over an influx of migrants into Europe.
Xi's comments to Cameron, made late on Thursday during a meeting at the British prime minister's country residence, echoed those from China's Foreign Ministry earlier this month.
On the last day of his visit to Britain, Xi arrived in Manchester to screams of delight from hundreds of supporters who were provided with "I love China" banners and flags.
Britain is courting Chinese involvement in investment projects in the north of the country as part of its plan to regenerate the region, where development has lagged the more prosperous southeast.
Hainan Airlines Co Ltd, China's fourth largest carrier, said it would start operating a Manchester to Beijing route from June, which Manchester Airports Group said would bring 250 million pounds worth of "economic benefits" to the British economy over the next 10 years.
Manchester Airports Group also launched a China cluster intended to provide a British base for Chinese businesses at its nearby business park, Airport City.
Britain has laid on its highest level of diplomatic charm for the Chinese delegation, including a stay at Buckingham Palace and a state banquet with Queen Elizabeth.
A soccer fan, Xi also visited an academy run by Premier League soccer club Manchester City. He met former City players, Patrick Vieira and Mike Summerbee, and watched a training session.
But critics say Cameron is doing little to persuade Beijing to stop selling cheap steel which has hurt Britain's struggling steel industry and turning a blind eye to China's human rights record.
Prominent Chinese dissidents accused British police of being heavy-handed after an exiled Chinese democracy activist and two Tibetan women were arrested at a protest during the visit.
The prime minister says the visit has already sealed almost 40 billion pounds ($62 billion) in business deals, including the financing of nuclear power stations which critics say is exposing sensitive industries to Chinese control.
Western spymasters accuse China of sponsoring hacking of global companies - a charge Beijing denies.
Finance minister George Osborne said the visit had secured Britain's place as "China's strongest partner in the West", a position that enabled officials to raise "difficult issues".
"A partnership is a relationship where we do things together like build nuclear power stations, invest in modern science, regenerate cities like Manchester," he told Sky television.
"A partnership is also where you can have frank discussions about issues like the future of steel making, or cyber security or indeed human rights."
Additional reporting by William James, writing by William Schomberg and Elizabeth Piper, editing by Peter Millership