Obama's nuclear fear over Pakistan

Barack Obama is to seek a guarantee from the Pakistani government that the country's nuclear arsenal will be kept safe from Taliban insurgents.

The US President will tomorrow urge President Asif Ali Zadari to face down the extremists amid growing international fears about the instability of the country.

White House spokesman Robert Gibbs said the volatile situation in Pakistan was now of the "highest priority" to the Obama administration.

Taliban extremists are camped less than 60 miles from Pakistan's capital Islamabad after the government allowed Islamic sharia law to be imposed in the Swat Valley.

They have since pushed further and Pakistani forces have launched counter-attacks.

US security advisers fear that extremist sympathisers in Pakistan's military or intelligence services could tip off militants to the movement of nuclear weapons from their guarded locations.