Libya’s improved image after decades of isolation is at risk if its Supreme Court rules on Tuesday to put six foreign medics to death for infecting more than 400 children with HIV.

Five Bulgarian nurses and a Palestinian doctor will hear in their appeal in Tripoli whether they will be executed by firing squad or face a retrial after being convicted of deliberately giving HIV-tainted blood to 426 children at the Libyan hospital where they worked.

The European Union has called the death sentences a major obstacle to Libyan leader Colonel Muammar Gaddafi’s push to renew ties with the West. The EU does not accept the evidence under which the medics were convicted on scientific grounds.

The medics, who have been in prison since 1999, say they were forced to confess under torture. They say the North African country has made them scapegoats rather than admit the infections were caused by poor hygiene standards.

Bulgaria, which is set to join the EU in 2007, could become a future obstacle for oil-producing Libya’s relations with the bloc.

“If (Gaddafi) executes them, he loses all sorts of leverage on Bulgaria and the West,” said Gergana Noutcheva, research fellow at the Centre for European Policy Studies. “Plus, they want compensation. If they kill the people, they’ll kiss the compensation goodbye,” she told.

Gaddafi, a pariah for much of his 35-year rule because the West accused him of terrorism, has improved his standing after announcing in 2003 he would abandon the pursuit of nuclear, chemical and biological weapons.

Tripoli has also agreed to pay $2.7 billion to the families of Lockerbie crash victims and has taken responsibility for the 1988 Pan Am plane bombing over Scotland.

Following Libya’s call that more compassion be shown to the victims, Bulgarian President Georgi Parvanov toured the hospital in Benghazi, which saw the outbreak of AIDS/HIV in 1999. His last-ditch diplomatic push came only days after the EU’s external relations commissioner visited.

GADDAFI OFFERED WAY OUT

Gaddafi is under intense pressure from the children’s families who demand punishment for a tragedy that Libya says has so far killed 50 children in a city where tribal roots run deep.

“We want a solution that satisfies the families of the dead children, the infected children still alive and those sentenced to death,” Foreign Minister Abdel-Rahman Shalgam told.

Letting the nurses go without compensation could put the spotlight of guilt on the shortcomings of Libya’s health system.

The Balkan state and its allies are seeking avenues to offer Gaddafi a way out of the standoff, by providing medical equipment, health experts, and some financial aid.

“We believe the action plan and the key international players, the United States and the EU, will meet the needs of the families in terms of treatment and medical help,” Bulgaria’s Deputy Foreign Minister Gergana Grancharova told Reuters.

This could possibly satisfy both parties - Tripoli could call it compensation, Sofia a humanitarian gesture - and possibly secure the nurses a retrial followed by a release.

EU diplomats say a retrial is more likely given that a separate trial is under way of nine Libyan policemen and a physician charged with torturing the medics into confessing.

Libya wants to join a EU economic partnership with Mediterranean region countries, which could bring it trade and aid. Resolving the issue of the medics is a condition if the EU is to give Tripoli approval to join.

“Of course we will go on talking and tomorrow will be a very crucial day. ... For the time being all my messages have been passed, now of course we have to see the Libyan reaction,” said EU External Relations Commissioner Benita Ferrero-Waldner.

No one expects a quick breakthrough through, least of all Ivan Nenov, husband of condemned nurse Nasya Nenova.

“I do not expect the case to be over on May 31, no matter whether the verdicts will be confirmed, or the trial be sent back for additional investigation,” he told.

“I do not want to hold out hope for their release, because it hurts much more afterwards.”