BEIRUT: Lebanon moved a step closer to political meltdown as Prime Minister-designate Omar Karami resigned for the second time in two months and the country's opposition vowed to organise street demonstrations if next month's elections are delayed. Karami chose Lebanon's unofficial National Unity Day to announce his consultations to form a government had "once again reached a dead end", but insisted parliamentary elections, could still be held on time.

He said: "I will not accept a third designation under any condition. The opposition has been saying that we are scheming to delay the elections and if I were to accept a third designation, I would be proving them right."

Speaking to reporters later in the day, Karami said: "I couldn't care less about the elections anymore. Nothing is worth it anymore."

He added: "We have worked through very difficult security restrictions and economic difficulties. A while ago, three rigged cars were found, one on its way to the South. This is enough."

Karami's announcement leaves Lebanon in a political limbo. President Lahoud said he would begin consultations with MPs to appoint a new prime minister designate on Friday.

Karami's failure to form a government triggered accusations from the country's opposition that the bickering is a deliberate ploy to delay next month's polls.

Parliament's four year term ends on May 31, but Lebanon's Constitution requires it to announce polling day at least one month before elections take place.

Beirut MP Walid Eido, an ally of assassinated former Premier Rafik Hariri ally, slammed the authorities for violating the legal deadline for the elections.

He said: "We want to assure them that no matter how long the delay, the Lebanese people will remain united for sovereignty and national unity."

On Tuesday night, the U.S. State Department warned holding the elections on time was more important than the immediate departure of Syrian troops from Lebanon.

The pro-Syrian Karami's latest departure comes amid cracks in the loyalist camp.

Other pro-Syrian political heavyweights made his task impossible following fighting over ministerial posts.

Karami said he will be abandoning the Ain al-Tineh loyalist camp because it had failed to provide him with the required backing to form a Cabinet.

But he denied any quarrel with Speaker Nabih Berri, the main sponsor of Ain al-Tineh, or with President Emile Lahoud.

Leading opposition MP Nassib Lahoud said the opposition will resort to street demonstrations to ensure next month's elections take place on time.

His threat was echoed by Chouf MP Marwan Hamade, one of the closest allies of opposition leader Walid Jumblatt.

Aley MP Fouad Saad, another Jumblatt ally, slammed the continuing delay in forming a Cabinet capable of overseeing the polls.

He said: "The ongoing consultations, the holidays, the mourning periods, the trips and the quarrels are all excuses to get out of the elections."

The most likely candidates to follow Karami into the premiership appear to be outgoing Economy Minister Adnan Qassar and former Premier Rashid Solh, both viewed as neutral figures.

Beirut MP Mohammed Qabbani, a close ally of slain Premier Rafik Hariri, whose brutal assassination on February 14 triggered the huge wave of public demonstratons and galvanised the country's opposition said: "Until now, the opposition's choice is not to take part in the consultations or to participate in a new Cabinet. But I stress that it is until now."

With Jumblatt and other opposition MPs in Strasbourg meeting European Parliament officials, the opposition has not yet scheduled a meeting to determine how to proceed.

The opposition's street protests and "people power" forced Karami to resign on February 28.

But following his resignation he was reappointed and given the task of forming a transitional government to bring Lebanon into the elections.

The ill-fated Karami had announced he would unveil the Cabinet lineup on Monday, but failed because his allies quarreled over ministerial posts.

The new Cabinet must draft the electoral law, a process that might take several weeks; it must also supervise the polls, which usually take place over four separate weekends.

Until a new Cabinet is formed, Karami's current Cabinet will remain in its capacity as caretaker government.

Annotazioni − With additional reporting by Nafez Kawas and with agencies.