Libya’s new rebel rulers were hailed by world leaders in Paris on Thursday and won a promise of a UN state-building mission, as fugitive strongman Muammar Gaddafi issued a new barrage of threats.

Forty-two years to the day since Gaddafi stormed to power in a coup, senior envoys from 60 countries met the leaders of the revolution that overthew him to endorse the fledgling regime and offer practical support.

The Elysee Palace guest list was a victory in itself for the rebel National Transitional Council, as once sceptical Russia and China and Libya’s reluctant neighbour Algeria agreed to extend their backing to the new government.

As the talks began, UN Secretary General Ban Ki-moon said he would work with the Security Council to agree terms for an immediate United Nations mission to deal with a possible humanitarian crisis and help rebuild the state.

“Our most immediate challenge is humanitarian,” he said. “Roughly 860,000 people have left the country since February, including skilled guest workers. Public services are under severe strain, including hospitals and clinics.

“There is a major water shortage. Meanwhile, sporadic fighting continues, particularly in the country’s south,” he said, adding that NTC, Arab, African and European leaders had all endorsed his plan.

While the mood was upbeat, US Secretary of State Hillary Clinton sounded a note of caution, urging the rebels to beware extremism in their own ranks and safeguard seized arms dumps to avoid them falling into the wrong hands.