COLOMBIAN President Juan Manuel Santos sought talks with Marxist guerillas and their pro-war opponents on Tuesday night to salvage a hard-won peace accord after voters rejected it in a referendum.

Mr Santos also extended the ceasefire with the Revolutionary Armed Forces of Colombia (Farc) until October 31.

Farc leader Timoleon “Timochenko” Jimenez tweeted: “And after that, does the war continue?”

The August 29 truce was originally due to last until Sunday October 2’s national referendum on the peace deal.

Mr Santos held out the olive branch to his predecessors Alvaro Uribe and Andres Pastrana, who led the rejectionist campaign that narrowly won Sunday’s plebiscite.

They were helped by Human Rights Watch — a US-based organisation funded by billionaire George Soros — which echoed their false claims that the deal granted impunity to guerillas accused of war crimes.

“Time is very important. We can’t prolong this process and this dialogue for a long time because we’re in a grey zone, a sort of limbo, that is risky and can wash away the entire process,” Mr Santos said.

Farc chief negotiator Ivan Marquez said that was true, “but it will be worse if we put peace in the hands of Uribe and Pastrana.”

Mr Marquez branded Mr Uribe “the leader of chaos.”

On Monday, the Farc, backed by leading peace campaigners, reiterated its long-standing call for a constituent assembly to be convened.

The following day, a government delegation led by chief negotiator Humberto de la Calle met with Farc representatives in the Cuban capital Havana for discussions on the reopening of negotiations.

The dangerous consequences of the No vote were highlighted when Farc negotiator and high command member Pastor Alepe tweeted that all units should begin to move to secure positions to avoid provocations.

The guerillas had already begun to move out of their mountain strongholds to halfway-house camps, where they were set to disarm and demobilise before returning to civilian life and politics.

But with the promise of an amnesty for most insurgents now scuppered, they can no longer be confident of living in peace.

Proposed talks with smaller rebel groups are also in doubt after the referendum result.

The National Liberation Army, which had offered to open peace talks with the government before the referendum, said the outcome had “exposed the obstacles to the advance of peace.”