A senior United Nations official has added his voice to calls for the expansion of the international peacekeeping force in Afghanistan, warning that the deteriorating security situation is thwarting the peace process.

Speaking at a meeting of the UN Security Council, Kieran Prendergast - the UN's undersecretary-general for political affairs - said the mandate for the force, Isaf, should be expanded beyond the Afghan capital, Kabul.

He said it should police any area where there is a clear pattern of emerging insecurity.

Mr Prendergast said that without security forces present, northern Afghanistan would lose support from aid agencies.

Aid workers there have been the targets of recent robberies and attacks, including the gang rape of one worker last week.

On Thursday, aid agencies made a similar plea for Isaf to be expanded, as Turkey took over control of the force from Britain for the next six months.

From the newsroom of the BBC World Service

*** PROBLEM: MORE THAN 28 WORDS IN SUMNARY ***