Prince Andrew should take a crash course in corporate responsibility and human rights awareness to enhance his role as the UK's trade ambassador, a prominent Foreign Office adviser has suggested.

The proposal to retrain the fourth in line to the throne reflects growing criticism of the Duke of York's style of business promotion and his close personal ties with corrupt and autocratic regimes, particularly in central Asia.

Tom Porteous, UK director of Human Rights Watch, is a member of the Foreign Office's advisory group created by William Hague to provide guidance about human rights issues and assess the ethical implications of British foreign policy.

"This is a classic case of unjoined-up government," Porteous said. "The government says it is committed to the rule of law, corporate responsibility and human rights around the world. So it should be promoting British business on the basis of those principles. They need to give [Prince Andrew] a crash course in human rights and corporate responsibility. It's pretty clear that he hasn't really thought about these kind of things.

"There's a reputational risk here. Countries such as Turkmenistan [which the prince visited last April] have an appalling human rights record."

Last night it emerged that a former British ambassador has written to the government to express concerns about the prince as scrutiny intensifies around his dealings with a number of controversial characters and his role as Britain's trade envoy.

Retired diplomat Stephen Day, 73, a former ambassador to Qatar and Tunisia, confirmed that he had written to the foreign secretary about the issue.

"I wanted to express my concerns about these stories about the Duke's activities, particularly relating to Tunisia," he told the Press Association. "I think the government reacted splendidly to events in Tunisia, and I admire the position the government has taken over the protests in the Arab world. I think this is an unfortunate diversion."

The letter was leaked to the Daily Telegraph, which quoted Day as saying: "It takes a lot to bring former British ambassadors to criticise a member of the royal family in public, but it is surely now recognised that the Duke's activities are doing such serious damage to the royal family itself and to Britain's political, diplomatic and commercial interests that an entirely new role should be found for him as soon as possible."

One of the issues raised by the advisory group last year was whether the coalition's decision to make British business abroad a priority conflicted with its pledge to support human rights.

Amnesty International has called on the duke, who has visited Azerbaijan seven times since 2005 and met President Ilham Aliyev, to intervene on behalf of a jailed newspaper editor, Eynulla Fatullayev, who has been adopted by the organisation as a prisoner of conscience.

Kate Allen, the director of Amnesty International UK, who is also on the advisory group, criticised the regime. "President Aliyev's government exercises tight control over free speech in Azerbaijan," she said. "Street protests are effectively banned and newspapers can be shut down for saying the wrong thing."

The Queen is reported to have held private talks with Andrew about the mounting scandal over his trade dealings with despots for the government and his personal links to the US financier Jeffrey Epstein, who has been convicted of sex offences with young girls.

The prince's spokesman refused to comment on the meeting, said to have taken place at the Queen's private apartments at Buckingham Palace on Tuesday, after more than two weeks of daily reports criticising his conduct and judgment as the UK's international trade envoy.

"I understand that she asked him if any more stories are going to come out in the next few days," the Daily Mail reported a senior aide as saying. "If the answer was yes, then his position will be untenable. I suspect he will make a decision in the next 48 hours or so."The newspaper said the Queen was concerned that scrutiny of the duke was overshadowing preparations for the wedding next month of Prince William and Kate Middleton, which the royal family hopes to use to increase public support.

But backing for the prince came from Sir David Tang, the Hong Kong restaurateur and businessman. He met the prince before his visit last October to promote business interests in Hong Kong.

Meanwhile, GeneWatch UK, which has campaigned against the police national DNA database, has disclosed that the UK Forensic Science Service is involved in a plan to DNA-test the entire population of the United Arab Emirates, under a contract signed in the presence of Andrew in 2006.

Dr Helen Wallace, of GeneWatch UK, called on ministers to scrap the contract under which a universal DNA database is to being built and linked to a national identity card scheme. "This would allow the Emirates to track every citizen and identify their relatives, a frightening prospect for dissidents and women," she said.