Colombian government negotiators and Marxist rebels have delayed their departure for peace talks in Norway aimed at ending nearly half a century of conflict.

A Norwegian government spokeswoman on Tuesday said that both parties still plan to arrive in time for their only publicly scheduled event on Wednesday.

Colombian officials, expected to have arrived in Norway over the weekend, will not come until Tuesday because of "logistical difficulties", the spokeswoman said.

It remained unclear when the Revolutionary Armed Forces of Colombia (FARC) would arrive.

The sides agreed to start talks in the first two weeks of October but had already delayed their arrival once to iron out details for discussions, which will he held under the principle "nothing is agreed until everything is agreed".

Arrest warrants

FARC leader Timoleon Jimenez told RCN and "La FM" radio in Colombia that there had been logistical delays in getting Ivan Marquez, a member of the seven-member secretariat and FARC negotiator, to Cuba and other issues regarding arrest warrants.

"According to the prepared schedule for pick up, our comrade's group was the last. For security reasons, our people do not move to the site until the time and date to pick them up is confirmed," Jimenez, also known as Timochenko, said.

Timochenko said that delays in lifting international arrest warrants for some FARC delegates were also a source of the lag. The interview was broadcast on Monday.

Timochenko responded to pre-written questions, and sources at the local media stations said that the recording was received early on Monday and was likely made on Sunday.

The rebel leader, who took over the FARC after the previous leader was killed by Colombian forces in 2011, did not say whether Marquez had made it to Cuba yet nor when the FARC delegation was expected in Norway, but reiterated the rebels' commitment.

"We'll arrive in Oslo or wherever the installation (of talks) is performed," he said.

"The table in the name of reconciliation of Colombians is a reality, the desired space to get on the road to peace and social justice is open."

Norway, which has acted as a negotiator between the sides for years, declined to discuss the delay and a foreign ministry spokesperson said the sides still plan to attend a press conference on Wednesday, their only public event.

Norway and Cuba have agreed to act as guarantors at the talks while Venezuela and Chile would "accompany" the talks.

‘Strong likelihood of an agreement’

Timochenko confirmed earlier reports that Dutch national Tanja Nijmeijer, alias Alexandra, would make up part of the FARC negotiating team.

The newspaper El Espectador said Colombia refused to accept her because she was not a Colombian citizen. Rebels, however, argued that the terms of their agreement allow them to freely pick the members of their team.

A 10-year military offensive has weakened the FARC but has been unable to end the conflict, leaving President Juan Manuel Santos vulnerable ahead of elections in 2014. 

Peace talks have already failed several times in the past.

Negotiations in Oslo are expected to focus on laying the groundwork for later discussions and the parties are then expected to move to Havana for the substantive part, which will focus mainly on land, drugs and political participation.

"We see a strong likelihood of an agreement some time by spring of next year, as both the FARC and President Juan Manuel Santos will probably be keen to come to an agreement before the 2014 presidential elections approach," Heather Berkman, an analyst with Eurasia Group, said in a research note.

"Given the government's success in reducing FARC troop numbers, eliminating leaders, and diminishing the armed group's morale over the last decade, as well as lessons learned from previous (failed) attempts at peace talks, there is strong potential for the negotiations to yield a real peace agreement."