Bomb disposal experts who defused the device said it had failed to go off only because a battery had failed.

Our intervention is motivated by the prevarication of the French state which continues to extend the policy of eradication against our community

FLNC statement

A Corsican separatist group, the FLNC, said it was responsible for planting the device.

It said it was also behind a bomb alert at a navy building in Nice on Monday, and two attacks on farms in Corsica the night before.

Anti-terrorism experts had already suspected Corsican extremists, after finding a scrap of the island's "Corse Matin" newspaper on the device.

The bomb had been set to go off early on Monday outside the Kleber Centre - which belongs to France's foreign ministry.

The centre was due to be the venue for a Middle East peace conference on Wednesday, which had raised questions over whether the device had been aimed at senior Palestinian or Israeli representatives who were due to attend.

But the communique from the FLNC appears to have ruled out any Middle East connection.

The FLNC, which represents four Corsican separatist groups, announced a ceasefire last December, after French Prime Minister Lionel Jospin launched a new political initiative on the island's future.

'Prevarication'

The group said in its communique on Tuesday that the ceasefire was intact, but blamed the French Government for moving too slowly towards a political solution.

"Our actions do not mean the ceasefire is over," it said.

"Our intervention is motivated by the prevarication of the French state which continues to extend the policy of eradication against our community."

The building targeted by the attack hosted the Vietnam peace talks in the early 1970s and the second round of talks on Kosovo's future early last year.