United Nations (PTI): Top UN official and veteran Indian diplomat Vijay Nambiar's talks with the Sri Lankan leadership have resulted in some movement in efforts to secure safe passage for civilians trapped in war zone in the island's north, the world body has said. 

"We do feel that in his discussions with Government officials there's been a little bit of movement forward in terms of trying to obtain the release of the civilians who are currently trapped in the conflict zone," said Farhan Haq, Associate Spokesperson to UN Secretary General Ban Ki-moon. 

"But those efforts will need to continue," Mr. Haq told reporters in response to a question on Friday. 

Mr. Nambiar, the Chief of Staff of the UN Secretary General, met Sri Lankan President Mahinda Rajapaksa on Friday in Colombo, a day after holing talks with Secretary of Defence Gotabaya Rajapaksa during his visit to the island nation. 

The UN's effort is concerned on two different levels, Mr. Haq said. "On the one hand, certainly we have repeatedly asked for the Government of Sri Lanka not to fire its heavy weapons and heavy artillery in the conflict zone," he said, adding that it is part of the effort designed to see what can be done to have innocent civilians leave that area. 

"The other part of that effort, of course, is that the Liberation Tigers of Tamil Eelam (LTTE) will need to allow the civilians who wish to do so to leave freely. We're trying our best both in our public statements and in our other efforts to work on both fronts," Mr. Haq said. 

When asked if Nambiar is in touch with the LTTE, Mr. Haq said: "I don't have anything to say on that at this moment." 

The UN remains deeply concerned about the plight of the civilian population still trapped inside the conflict zone. 

Those fleeing into Government-controlled regions provide similar accounts of the dire humanitarian conditions prevalent inside the area, he said. 

Calling on the LTTE to immediately allow these people to move to areas where they feel safe, the UN also urged both parties to the conflict to adhere to International Humanitarian Law and ensure that the safety of the innocent civilian population is the top priority. 

Meanwhile, the United Nations High Commissioner for Refugees (UNHCR) in Sri Lanka has stepped up its emergency response in the north, where displacement numbers are growing as a result of heavy fighting between the military and LTTE. 

The latest estimates show that more than 63,000 people have fled the conflict zone in the north-eastern coastal pocket and are being accommodated at several transit and internal displacement sites in the districts of Vavuniya, Jaffna and Mannar, the UN spokesman said. 

The Sri Lankan Government, meanwhile, said some 1,800 displaced persons with special needs, particularly the elderly, have been released from the sites, and some 1,345 separated families have so far been reunited.