Right-wing Salvadorean presidential candidate Norman Quijano - who may have lost narrowly in Sunday's election - claimed that his party was on a "war footing" and ready to "to fight with our lives, if necessary" to claim the presidency.

The election pitted governing Farabundo Marti National Liberation Front (FMLN) candidate Salvador Sanchez Ceren against Mr Quijano of the Nationalist Republican Alliance (Arena), which was previously linked to oligarchy-financed death squads.

Preliminary returns from nearly all polling stations showed Mr Sanchez Ceren with an advantage of just 7,000 votes - 0.2 per cent of the approximately 3 million ballots cast.

Supreme Electoral Tribunal president Eugenio Chicas said that the race was "extremely tight" and that neither candidate should claim victory.

"This tribunal orders neither party to declare itself the winner, in light of results that are so close that only the final count can decide."

The election was held to produce a successor to FMLN president Mauricio Funes, a former journalist who had been sympathetic to left-wing guerillas but had played no role in the civil war.

Mr Sanchez Ceren, a former guerilla commander who helped negotiate the 1992 peace accords that ended El Salvador's civil war, was in no doubt of his victory.

He told his opponent: "The men and women of El Salvador are the ones who decide and, if you don't accept the result, you are violating the will of the people.

"I say to my adversary, to his party, that my administration will welcome them with open arms so that together we can build a new country."

In contrast, Mr Quijano abused the election authorities, alleging fraud and suggesting that the armed forces should become involved, reviving memories of the civil war that cost the lives of 76,000 people.

"We are not going to allow Venezuelan-style fraud, in the style of Chavez and Maduro. We have had our own recount, which shows we won," the former mayor for the capital San Salvador ranted.

Mr Quijano said that the Supreme Electoral Tribunal had "sold out to the dictatorship," declaring that "the armed forces are ready to make democracy."

The country's military top brass has made no comment so far on the elections.

The election authorities began a recount of the results .