U.S. Vice President Joe Biden says the Obama administration is focused on improving Pakistan's stability, safeguarding its nuclear weapons program and defeating al-Qaida militants, but officials first must ensure that the Afghan government does not fail.

In a televised interview Tuesday on MSNBC, Biden said the United States would be in what he called "real trouble" if the neighboring Afghan government collapses and creates a power vacuum.  He said it would be difficult to guess the response from countries such as Iraq, China or Russia.

The vice president also praised Pakistan for its ongoing military campaign against Pakistani Taliban groups, but he said the country still is not doing enough.
Recent news reports in the United States, citing anonymous U.S. intelligence officials, say Washington is pressuring Islamabad to allow drone strikes against militant targets outside of Pakistan's tribal areas and to kill or hand over wanted militants who are believed to maintain ties with Pakistan's spy agency.

The New York Times newspaper says U.S. officials have asked Pakistan to hand over Afghan Taliban commander Siraj Haqqani, who is widely believed to use Pakistan's North Waziristan tribal area as a sanctuary.  The newspaper says Pakistan is reluctant because it still considers the militant leader an asset to its spy agency.  

The New York Times says Pakistani leaders are skeptical about the prospects of success of the U.S. troop surge in Afghanistan, and want to be prepared for a regional alignment once U.S. forces leave the country.

Pakistan's military and intelligence services reject allegations that they maintain ties to militant groups.

On Monday, the top U.S. military officer said he is deeply concerned about what he called a "growing level of collusion between the Afghan Taliban and al-Qaida" and other extremist groups in Pakistan.

The chairman of the Joint Chiefs of Staff, Admiral Mike Mullen, said militant networks taking refuge in Pakistan's tribal regions have become more entrenched.

Some information for this report was provided by AP.