BEIJING - Britain says China has executed a Briton convicted of drug smuggling, after rejecting a string of appeals from the British government and his family, who say he was mentally unstable and unwittingly lured into the crime.

The British Foreign Office issued a statement early today condemning the execution of 53-year-old Akmal Shaikh.

He was the first European citizen executed in China in half a century.

Shaikh first learned his death sentence would be carried out from his visiting cousins yesterday, who made a last-minute plea for his life. They say 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.

British Prime Minister Gordon Brown had spoken personally to China's premier about his case.

"I believe we have done everything we possibly can," said Ivan Lewis, a Foreign Office minister, after meeting with the Chinese ambassador in London late yesterday. "We urge at this very late stage the Chinese government to do the right thing."

Two years ago, Shaikh, who relatives say used to be hardworking and devoted to family, was apparently living on the streets of Warsaw. But Gareth Saunders, a British teacher who lives in Poland, said Shaikh nonetheless maintained an "exaggerated positivism" that Saunders called both endearing and sad.

Saunders, who was one of the last people to see Shaikh before his arrest and who knew him as a colorful local character, said he helped out the fellow Brit by buying him coffee and singing backup when Shaikh insisted on recording his song for world peace, "Come Little Rabbit."

"He thought he had a gift with his voice, but it was clear to anyone listening he had no sense of timing, nothing," said Saunders, who was put in contact with reporters by Reprieve, a London-based prisoner advocacy.

The group, which had lobbied for clemency for Shaikh, said he was duped into trafficking drugs to China by men promising that he would attain fame with a hit single.

"He would have believed that for sure, about having a big hit in China," Saunders said.

The two last ran into each other in a Warsaw underpass when Shaikh told Saunders he was going to a country in central Asia and would be back in a couple of weeks.

Shaikh was arrested in 2007 for carrying a suitcase with almost 9 pounds of heroin into China on a flight from Tajikistan. He told Chinese officials that he did not know about the drugs and that the suitcase wasn't his, according to Reprieve.

He was convicted in 2008 after a half-hour trial. In one court appearance during his trial and appeal process, the judges reportedly laughed at his rambling remarks.

"We strongly feel that he's not rational and he needs medication," his cousin Soohail Shaikh had said. "We beg the Chinese authorities for mercy and clemency to help reunite this heartbroken family."

The execution of Shaikh, who had no prior criminal record, was the latest in an extraordinary series of Chinese actions that have led to widespread outrage, including Friday's 11-year prison sentence of a literary critic who cowrote a plea for political reform.

"It certainly does send a message, intended or not, that China doesn't really care what the international community thinks about how it handles criminal cases," said Joshua Rosenzweig, research manager for the U.S.-based human-rights group Dui Hua Foundation.

China had planned to tell Shaikh of his sentence 24 hours before it was to be carried out, Reprieve said. It is not unusual for China to wait until the final hours to notify inmates of their fate.

But his cousins, who visited the prison hospital in far western China where he was being held yesterday, broke the news first.

"He was obviously very upset on hearing from us of the sentence that was passed," Soohail Shaikh said.

The cousins were given a bag of Akmal Shaikh's belongings yesterday.

Chinese Foreign Ministry spokeswoman Jiang Yu told a news conference last week: "Drug smuggling is a grave crime. The rights of the defendant have been fully guaranteed."