US Secretary of State Hillary Clinton says Pakistan's nuclear arsenal is currently safe, but Washington has concerns over what could happen if the advancing Taliban topples the government.
In an interview while visiting Baghdad, Mrs Clinton said the security of Pakistan's nuclear arsenal is an issue the US has adamant assurances about from the Pakistani military and government.
More than 1,800 people have been killed in a wave of Al-Qaeda and Taliban-linked extremist attacks across Pakistan since July 2007, when the military stormed the Islamist-occupied Red Mosque in Islamabad.
The United States this week voiced concerns over advances by the Taliban and said the issue was taking up a significant amount of President Barack Obama's time.
