China says Akmal Shaikh is a drug smuggler and must be executed Tuesday morning. But family and acquaintances say the 53-year-old Briton is 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.

Shaikh first learned of his death sentence Monday from his visiting cousins, who made a last-minute plea for his life. Prime Minister Gordon Brown has spoken personally to China's prime minister about his case, but there's little to suggest Beijing will relent.

Shaikh would be the first European citizen to be executed in China in half a century.

Two years ago, the man 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, told The Associated Press 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 has been lobbying 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've believed that for sure, about having a big hit in China," said Saunders.

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

"I think it's absolutely disgraceful," Saunders said of the death sentence. "I don't think he's in a position to defend himself."

Shaikh was arrested in 2007 for carrying a suitcase with almost 9 pounds (4 kilograms) of heroin into China on a flight from Tajikistan. He told Chinese officials he didn't 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," one of his cousins, Soohail Shaikh, said. "We beg the Chinese authorities for mercy and clemency to help reunite this heartbroken family."

The planned execution of Shaikh, who has no prior criminal record, is the latest in an extraordinary series of Chinese actions that have led to widespread outrage, including Friday's sentencing of a literary critic who co-wrote a plea for political reform to 11 years in prison.

"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's 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 is being held Monday, broke the news first.

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

He told reporters at the Beijing airport late Monday that Shaikh, who is of Pakistani descent, used to be a hardworking family man. "Then we lost track of him."

Last-minute appeals are almost never granted in China, which executes more people each year than all other countries combined.

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

By now, any decision to stay Shaikh's execution would be a political one, taking into account the damage his death could do to relations with Great Britain, the European Union and others, Rosenzweig said. But chances were slim.

Though China is gradually switching to executions by lethal injection, Rosenzweig said he would likely be shot in the head.

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

Two British diplomats accompanied the cousins but said they were not authorized to speak to journalists.

"The Prime Minister has intervened personally on a number of occasions: He has raised the case with Premier Wen, most recently at the Copenhagen summit; and has written several times to President Hu," said an e-mail from the British government.

Britain has accused Chinese officials of not taking Shaikh's mental health concerns into account, with a proper psychiatric evaluation, as required by law.

"They're not even pretending to protect his rights," Rosenzweig said. "That really baffles me."

In London, some of Shaikh's family joined a vigil outside the Chinese Embassy. A cousin, Latif Shaikh, said Shaikh's mother, who is in her 80s, knows he's in prison but doesn't know he faces execution.

He said the shock could kill her. "This execution will take two lives without a doubt," he said.