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BEIJING - Britain's foreign secretary is in China to lobby for further nuclear sanctions on Iran and will seek to smooth rancour with Beijing over climate change talks and the execution of a British drug smuggler thought to be mentally ill.
David Miliband's visit is a further step in the push by Britain, the U.S. and others to persuade China to drop its opposition to a fourth round of sanctions to pressure Iran to suspend its uranium enrichment program.
China and Russia have been skeptical of the need for new sanctions, which U.N. diplomats say would target Iran's powerful Revolutionary Guard and toughen existing measures against its shipping, banking and insurance sectors.
However, recent statements from Russian diplomats are seen as indicating that Moscow may be losing patience with Iran and moving closer to supporting sanctions. That would leave China - which depends on Iran for much of its energy needs - as the only one of the five veto-wielding permanent Security Council members opposed to new sanctions.
Miliband was to inaugurate the $38 million British pavilion at the Shanghai Expo and visit a training base for Chinese U.N. peacekeepers on Monday.
He was to meet with his Chinese counterpart Yang Jiechi and Premier Wen Jiabao on Tuesday and deliver a talk at Beijing's Foreign Affairs University before leaving Wednesday.
The trip comes amid continuing friction between London and Beijing, played out through dueling accusations, diplomatic protests and statements in the media.
Ties bottomed out last December after China ignored personal appeals from British Prime Minister Gordon Brown not to execute 53-year-old Akmal Shaikh for drug smuggling. Shaikh's family said he was mentally unstable and was lured to China from a life on the street in Poland by men playing on his dreams to record a pop song for world peace.
Brown said he was "appalled" by the execution - China's first of a European citizen in nearly 60 years - prompting a warning from Beijing that such comments threatened to damage ties.
Even before that exchange, the two had clashed over December's U.N.-sponsored Copenhagen climate talks that ended without a binding agreement on emissions reductions.
In the aftermath, British climate change minister Edward Miliband - David Miliband's brother - published an editorial singling out China as the culprit behind the talks' near collapse.
The bilateral friction comes as China's relations with the United States have also been fraught with tension over U.S. arms sales to Taiwan, President Barack Obama's meeting with the Dalai Lama, trade issues and China's handling of the Iran nuclear issue.
While Beijing has lately cooled its angry rhetoric over such issues, a fence-mending visit to Beijing this month by U.S. Deputy Secretary of State James Steinberg and Senior White House Asia adviser Jeffrey Bader apparently produced no breakthroughs.
Beijing insists the U.S. is entirely responsible for the turbulence in ties and must take actions it does not specify to repair the rift.
Emboldened by its rising global clout and economic influence, analysts say the tough line taken by Beijing signals the communist government's growing willingness to confront those who challenge it.
