Cécilia Sarkozy set off on a mercy mission to Libya yesterday and found herself at the centre of a row over her role as the first lady of France.

Travelling to Tripoli for the second time in two weeks, the wife of President Sarkozy placed herself at the heart of an international drive to free five Bulgarian nurses and a Palestinian doctor who have been held since 1999 and convicted of infecting hundreds of children with Aids.

President Sarkozy is expected in Tripoli tomorrow, hoping to greet the nurses upon their release, accompanied by his wife. But Mrs Sarkozy’s foray into diplomacy, which is without precedent for the wife of the French head of state, has sparked controversy.

Her intervention comes at a delicate stage of negotiations with the Libyan Government. The country’s Supreme Judiciary Council has commuted their sentences of death by firing squad to life imprisonment after payment of $1 million (£486,000) in compensation to each of the victims’ families.

But yesterday Libya was reported to have added new demands for the nurses’ release, including normalised ties with the European Union.

In Paris critics say that Mrs Sarkozy’s Libyan mission is an attempt to carve out a prominent position for the former model and communications consultant, who has, at best, limited experience of international diplomacy. In Brussels officials deplored what was perceived as a brazen attempt to seize the glory from the EU, which has taken the lead role in negotiating the nurses’ release.

Benoît Hamon, the French Socialist Party spokesman, said: “You can’t at the same time say you want to beef up Europe’s diplomatic muscle and then try to steal the victory just when the EU’s about to pull something off, and all so that Madame Sarkozy can strut around on the republican stage.

“It is extraordinary that just because Mr Sarkozy wants to find a role for his spouse, the EU should have to drag along the wife of the President in a difficult negotiation.”

Pierre Moscovici, a former Socialist European affairs minister, said that President Sarkozy was playing “the cuckoo in the nest” and trying to grab the limelight in Libya. He said: “He’s laying his eggs in someone else’s nest. Because basically France has played no part in all of this.”

Bernard Kouchner, the French Foreign Minister, also showed his irritation over Mrs Sarkozy’s intervention. Asked if he planned to go to Tripoli, he replied: “Don’t you think there are enough people there already?”

The controversy flared up amid reports that Mrs Sarkozy, 49, had been reluctant to assume the first lady role after months of marital tension. She agreed to do so only after anguished discussions with her husband and other family members, French newspapers have claimed. Paris was awash with speculation that the couple were on the pointing of splitting up after she failed to vote for him in the second round of the presidential election in May. The rumours surfaced again when she accompanied him to the G8 summit in Heiligendamm, Germany, last month, and then left early.

But French government spin-doctors say that she was merely asserting the independence that will help her to enshrine the modern French woman. With her Christian Dior and Prada dresses, black mini and headstrong character, she will prove a popular first lady, they say.

“If you liked Jackie Kennedy, you’ll love Cécilia Sarkozy,” the French President is reported to have told friends on the night of his election.

Initially Mrs Sarkozy adopted a relatively low profile, although she attracted unwanted publicity for using a credit card charged to the presidential budget to pay restaurant bills. However, she let it be known that she would not be satisfied with the charity work that was the main task of previous French first ladies.

After she appointed a former Disney press officer to run her communications, Paris Match magazine said that she was “in a hurry to make herself useful.” As there is no official status for the first lady under the French constitution, Mr Sarkozy said that his wife would have to find her own path. “That happens naturally, calmly, in small steps,” he said.

Mrs Sarkozy arrived in Tripoli on Sunday night accompanied by Benita Ferrero-Waldner, the European Commissioner, who was credited, with Tony Blair, with negotiating the outline agreement for the nurses’ release with Colonel Gaddafi, Libya’s leader.

Mrs Ferrero-Waldner was said to have been furious to read about Mrs Sarkozy’s first visit to Tripoli in the press.

Rise of the first ladies

— The model for generations of active First Ladies, Eleanor Roosevelt was determined to shrug off the passive role. She travelled America alone while campaigning for her husband’s New Deal policies and for civil rights, wrote a daily column and played a key role in the development of the United Nations

— Eva Peron attained power in Argentina as a union activist during her husband’s presidency and also established a political party. She almost ran alongside her husband as a vice-presidential candidate in the 1952 election

— Raisa Gorbachev’s academic and political prominence distinguished her from a series of unmemorable Russian first ladies. Public appearances and speeches softened the image of an “evil empire”

— Mehriban Aliyeva, first lady of Azerbaijan, is also a Vogue model, a qualified physician, a Unesco Goodwill Ambassador, an internationally decorated patron and president of several charitable foundations, and a member of the national assembly

— Presidential candidate Hillary Clinton’s role as America’s First Lady began with a disastrous attempt to expand healthcare. She made few friends and even less progress chairing the short-lived Task Force on National Health Care Reform

Sources: Unesco.org; eurasianet.org; www.whitehouse.gov; Raisa Gorbachev Foundation; www.evitaperon.org

Times Recommends

• Green activists 'are keeping Africa poor'
• 'Delayed justice' fear for OJ Simpson
• Sex and the sari