Diplomats are cautiously optimistic that attempts to release five nurses and a doctor jailed for infecting children with HIV are close to fruition despite a ruling by the Libyan Supreme Court yesterday upholding the death sentences of the six.

The Bulgarian nurses and Palestinian doctor, who have been held since 1999, did not attend the court in Tripoli to hear that their latest appeal had failed. They were convicted in 2004 of infecting 426 Libyan children with the virus that causes Aids.

Political leaders across Europe expressed their disappointment but diplomats were hopeful that a complicated financial deal would result in the sentence being commuted as early as next week. Libya’s highest court, the government-controlled High Judicial Council, announced that it would sit on Monday to review the case. One EU diplomat told The Times: “A massive amount of work is going on. It is a giant jigsaw puzzle.”

The Libyan leader, Colonel Muammar Gaddafi, has the power to pardon the medical staff and has been lobbied by President Bush, Tony Blair and the EU, which Bulgaria joined this year.

The six maintain that they were forced to confess under duress to the Aids infections, which occurred in the 1990s because of poor hygiene practices at a hospital in the Mediterranean city of Benghazi. Fifty-six of the children have since died.

The children’s families have asked for €10 million (£20 million) compensation for each child, much more than the EU and Bulgaria have been prepared to pay. The Supreme Court ruling came a day after the Gaddafi Foundation, a charity run by a son of the Libyan leader, said that it had reached agreement with the families that “puts an end to the crisis”. The deal is understood to include funding for a new medical centre. If the death sentences were to be commuted, the medical workers could return to serve them in Bulgaria. In preparation, the Palestianian doctor was awarded a Bulgaran passport last month to simplify a group release. While Libya has referred to compensation, Bulgaria has rejected this as implying that the six were guilty.

Experts said that yesteday’s ruling completed the role of the judiciary in the highly politicised trial and that Libya’s executive could now step in.

Zdravko Georgiev, a doctor and the husband of Kristiana Valcheva, one of the condemned nurses, said: “Only God knows what will happen from now on. We have always hoped for a miracle and we will continue to pray for one.” Mrs Valcheva’s mother, Zorka Anachkova, said: “My only hope lies with the solidarity of the whole world with the problem.”

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