Colombo - Sri Lanka's President Mahinda Rajapaksa has told UN Secretary General Ban Ki-moon that the suffering of civilians in the northern part of the country was the "sole responsibility of the Tamil rebels who are holding them as a human shield," the president's office said Friday. The president conveyed his position during a telephone conversation with the UN secretary general on Thursday during Rajapaksa's official state visit to Libya.

The telephone conversation was initiated by Ban to discuss the prevailing humanitarian situation regarding Tamil civilians in the north of Sri Lanka, the president's office said.

The UN chief had expressed his concern about the thousands of civilians trapped in the No Fire Zone, an area of some 20 square kilometres which has been unilaterally declared by the Sri Lankan government for civilians.

Rajapaksa informed Ban about civilians who were fleeing the Liberation Tigers of Tamil Eelam's (LTTE) hold in the rapidly diminishing land they control.

President Rajapaksa repeated his call on the UN and all interested parties to bring increased pressure on the LTTE to give the people the freedom to leave the affected area, the president's office said in a statement.

Meanwhile, the Defence Ministry Friday said that troops were poised to rescue thousands of civilians in the No Fire Zone held hostage by the rebels.

"Troops have identified the best accessible routes for the civilians to come out of the NFZ and established rescue points there," the ministry said.

"Troops continuously keep the civilians informed about the safe routes to the cleared areas as they open up more escape routes to the civilians by removing terrorists blockades," the ministry said.

The army has been using public address systems positioned at several locations closest to the NFZ to convey this information to the civilians," the defence ministry added.

Meanwhile, Tamil rebels claimed the military was continuing to fire into the No Fire Zone, causing deaths and injuries to civilians there, but the military is denying the claim.

The government estimates there are at least 50,000 civilians in the area, but UN agencies say the figure could be as much as 100,000.

The civilians there have been complaining of shortages of medical supplies, though food is being sent with the assistance of the International Committee of the Red Cross
(ICRC).

The military says they are in the final phase of crushing the rebels who have been fighting for an independent homeland for minority Tamils in the north eastern parts of the country for more than 25 years.(dpa)