Colombian President Juan Manuel Santos, in a close re-election fight, promised Wednesday to abolish the military draft if a peace agreement is reached with FARC rebels.

"Once the conflict ends the obligatory military service is finished," he said in an interview with BLU Radio.

The pledge comes as Santos finds himself virtually tied in the polls with rival Oscar Ivan Zuluaga less than two weeks before the country's run-off presidential elections June 15.

Zuluaga beat the incumbent in the first round of voting last month and is a vehement opponent of the peace talks with the FARC, the centerpiece of Santos' presidency.

The dispute has lately spilled over into a broader debate over the implications of peace for the Colombian military and security forces.

On Tuesday, Colombia's chief negotiator in the Havana talks, Humberto de la Calle, appealed to soldiers and police not to be turned against the peace process by opposition "disinformation."

Santos' running-mate, German Vargas, complained that some members of the National Police were campaigning for Zuluaga in violation of a constitutionally mandated ban on their taking part in politics.

A recent controversial Santos TV ad targeted Colombian parents, asking if they would send their sons to war.

"It's easy to fight a war with other people's children," said the ad that kicked up a storm, with opposition critics insisting it demeaned the sacrifice and service of those in uniform.

Each year, 120,000 young men are drafted into the Colombian military, which has been at war with the FARC for 50 years.

University students are exempted from the draft, however, so most of the recruits are youths from poor or low income families.

The FARC, meanwhile, said from the Cuban capital that it was seeking a change in Colombia's "military doctrine," which a spokesman said was "US-made."

"We have still not reached the point of speaking about a reduction or disappearance of the two forces," said FARC delegate Jesus Santrich, referring to the military and the guerrillas.

"Surely the moment will come to talk about that, but we are not there yet," he said.

The peace talks began in November 2012, but some major issues remain unresolved, notably the surrender of weapons by the FARC, compensation for victims of the conflict, and whether a comprehensive peace agreement should be put to a referendum or ratified in some other way.