Colombia's last active rebel group said Monday it will resume its guerrilla war on May 1, ending a one-month unilateral ceasefire over the coronavirus pandemic.

The ELN said in a statement it was resuming military operations because of a lack of response to its March 30 ceasefire announcement by the conservative government of President Ivan Duque.

It accuses Bogota of "lacking the will" to resume stalled peace negotiations in Havana, Cuba and is demanding safe passage for its negotiating team to allow them return to Colombia.

"It is clear that we are facing a bellicose government, deaf to the calls of Pope Francis and the Secretary General of the United Nations, and blind to the humanitarian tragedy being suffered by the Colombian people," the organization said, referring to recent appeals by the UN chief and the pope for an immediate ceasefire in global conflict.

So far, 244 people have died from COVID-19 among a total of 5,400 cases in Colombia.

Colombian soldiers at a ceremony to present a new battalion in Medellin on February 11,2020
Colombian soldiers at a ceremony to present a new battalion in Medellin on February 11,2020 AFP / JOAQUIN SARMIENTO

UN special envoy Carlos Ruiz Massieu said there had been "significant respect" for the ELN truce, and urged it to "extend the ceasefire".

The ELN, which is said to operate in about 10 percent of the country, has some 2,300 combatants and an extensive network of supporters in urban centers.

It is the last formal guerrilla group left in the country after the government reached a peace agreement with the larger Revolutionary Armed Forces of Colombia, or FARC, in 2016.

Peace negotiations began with the ELN the following year, first in the Ecuadoran capital Quito, and later in Havana.

But Duque, a conservative who succeeded Juan Manuel Santos -- who delivered the FARC peace deal and opened discussions with the ELN -- ended the talks after a January 2019 car bomb attack on a Bogota police academy that killed 21 recruits.

Duque has said he would only reopen talks if the ELN releases all its hostages and ceases its "criminal activity."