The government of Colombia and the country's last active rebel force, left-wing National Liberation Army (ELN), will resume peace talks in just over a week, according to the lead state negotiator.

The return to the negotiating table was scheduled for last Wednesday but was put off because of an information-sharing meeting in Cuba between the ELN and the bigger leftist rebel group, FARC, which has already struck an accord with the government.

"Ecuador has generously hosted the peace talks between the Colombian government and the ELN, which will resume on May 16," Juan Camilo Restrepo, the Colombian negotiator, said on Twitter.

A visit to Colombia by Lenin Moreno, president-elect of Ecuador - due to take place on Monday - also pushed back the resumption of talks.

Restrepo said Moreno "will keep supporting the talks looking for peace in Colombia" as his outgoing predecessor Rafael Correa did.

In November, FARC, or the Revolutionary Armed Forces of Colombia, signed a peace deal with the government after four years of talks.

The ELN launched its peace negotiations in February.

It has an estimated 1,500 fighters, compared with FARC's 7,000.

Formal negotiations between the ELN and the government were delayed from November 2016 pending the release of a prominent politician the group held hostage for nearly 10 months.

READ MORE: Complaints over construction delays at FARC peace camps

More than five decades of conflict involving the two rebel movements, the army and right-wing paramilitary groups, have resulted in more than 260,000 deaths, the disappearance of tens of thousands, and the displacement of about six million people.

The ELN is considered a "terrorist" group by the US and the EU. It is believed to have extorted, bombed oil and electricity infrastructure and kidnapped hundreds of people in its 52 years of existence to raise funds for the war and put pressure on the government.

Colombia is the last country to see major armed conflict in the region. Peace with the two rebel groups could allow for economic development in previously rebel-held areas.