The Chinese ambassador Fu Ying has been summoned to the Foreign Office amid a growing row between the UK and China over the execution of a British man.

Akmal Shaikh, 53, a father-of-three from London, was executed in China after being convicted of drug smuggling despite claims he was mentally ill.

Foreign Office Minister Ivan Lewis told the ambassador "China had failed in its basic human rights responsibilities".

The Chinese Embassy said Mr Shaikh had no previous record of mental illness.

Mr Lewis said after the meeting: "I had a difficult conversation with the Chinese Ambassador today.

"I made clear that the execution of Mr Shaikh was totally unacceptable and that China had failed in its basic human rights responsibilities in this case, in particular that China's court had not considered the representations made about Mr Shaikh's mental condition.

"It is an important element of a mature bilateral relationship that we are able to speak frankly about issues on which we disagree and that those concerns are heard."

Mr Shaikh's execution by lethal injection took place despite repeated calls from his family and the British government for clemency.

Sally Rowen, of the legal charity Reprieve, said a report from a consultant forensic psychologist had diagnosed him with bipolar disorder and delusional psychosis.

Prime Minister Gordon Brown said he was "appalled" at the execution. However, China warned criticism of the case would harm UK-China relations.

Mr Shaikh's cousins Soohail and Nasir Shaikh, who travelled to China to visit him in prison and make a last-minute plea for clemency, said they were "deeply saddened, stunned and disappointed" by the execution.

They said: "We are astonished at suggestions that Akmal himself should have provided evidence of his own fragile state of mind.

"We find it ludicrous that any mentally-ill person should be expected to provide this."

His daughter Leilla Horsnell added: "I am shocked and disappointed that the execution went ahead with no regards to my dad's mental health problems, and I struggle to understand how this is justice."

Condemnations

In a statement issued after the execution, the Chinese Embassy said Mr Shaikh's rights "were properly respected and guaranteed" and British concerns were "duly noted and taken into consideration".

It said: "As for his possible mental illness which has been much talked about, there apparently has been no previous medical record."

A report from the official Chinese news agency Xinhua said that China's Supreme People's Court had not been provided with any documentation proving that Mr Shaikh had a mental disorder.

In a statement, Mr Brown said: "I condemn the execution of Akmal Shaikh in the strongest terms... I am particularly concerned that no mental health assessment was undertaken."

Conservative leader David Cameron echoed the condemnation, saying he "deplored and deeply regretted" the execution.

Mr Lewis, who had held last-ditch talks with the Chinese ambassador in London on Monday evening, said the execution made him "sick to the stomach".

He said the government had made 27 representations to China in two years, and believed it had done everything it possibly could.

A spokeswoman for the Chinese Foreign Ministry, Jiang Yu, told a press briefing in Beijing no-one had the right to comment on China's judicial sovereignty.

"We express our strong dissatisfaction and opposition to the British government's unreasonable criticism of the case. We urge [them] to correct their mistake in order to avoid harming China-UK relations," she said.

The legal charity Reprieve had taken up Mr Shaikh's case for the family.

Ms Rowen, of Reprieve, said it was "outrageous" Mr Shaikh had been killed.

"The Chinese's blatant refusal to even consider [his mental illness] is outrageous and totally inappropriate," she said.

Mr Shaikh is the first EU national to be executed in China in more than 50 years.

His body will not be repatriated to the UK, and Mr Lewis said Mr Shaikh had been buried quickly "in accordance with the Muslim faith".

'No excuse'

In its statement, the Chinese Embassy said Mr Shaikh was convicted of "serious" drug trafficking.

"The amount of heroin he brought into China was 4,030g, enough to cause 26,800 deaths, threatening numerous families," it said.

Mr Shaikh's family said he had been delusional and duped into a carrying a suitcase that did not belong to him when he was found with 4kg of heroin in Urumqi, north-west China, in September 2007.

His daughter has said drug smugglers in Poland convinced him they would make him a popstar in China.

Marjorie Wallace, chief executive of the mental health charity Sane, said the Chinese authorities had showed not only a lack of compassion, but a "profound ignorance" about how a mental illness such as bipolar disorder could affect a person's sense of reality.

"Mr Shaikh's lack of official medical records is no excuse for failing to give him a psychiatric assessment or offer him the treatment he needed," she added.

Charity MDF, The Bipolar Organisation, described the execution as "medieval rough justice" and an "absolute tragedy".

Spokesman Robert Westhead said: "The way the Chinese authorities have stubbornly failed to take account of this poor man's severe mental illness shows that China is still stuck in the dark ages."