A United Nations official in Afghanistan says Pakistan must to do more to stop Taleban leaders from staging attacks, as required by a UN resolution.

A deputy UN representative in Afghanistan, Christopher Alexander, told reporters Monday that resolution 1267 requires all states to arrest and freeze the assets of people listed as terrorists. But Alexander said the resolution, as it relates to Taleban militants, is not being implemented.

He said of the 142 Taleban leaders on the list, only a handful have been captured and the vast majority continue to organize and operate within both Pakistan and Afghanistan.

The UN official said both Pakistan and Afghanistan must work harder to deny sanctuary to Taleban insurgents and other militant groups.

Afghanistan and Western countries say militants are operating from bases inside Pakistan. But Islamabad insists it is doing all it can to stop them.

That includes a recent Pakistani proposal to mine and fence parts of its border with Afghanistan to stop militants from conducting cross-border attacks.

Some information for this report was provided by AP and Reuters.