Islamabad, Dec 19 : A bipartisan group of American experts on Pak-US relations has called for a rethink in Washington's approach towards Islamabad, depicting a dismal picture of the country and expecting Pakistan to prove to be the single greatest foreign policy and national security challenge for President-elect Barack Obama.

The Pakistan Policy Working Group report reviewed and endorsed by Richard Armitage, former US Deputy Secretary of State, and Lee Hamilton, former US Representative and Co-Chair of the 9/11 Commission, has cautioned that because of intensifying political, economic and security crisis in Pakistan, American interests were more threatened.

The purpose of the report titled `The Next Chapter - The United States and Pakistan - was to offer ideas to the next US administration on managing this critical partnership, which the group believed required `heightened attention', Dawn reported.

The 54-page report was launched at a ceremony in the US Embassy here on Thursday with a strong message that there was little time for the Americans to waste and their options in Pakistan were diminishing rapidly.

"Making progress in the US-Pakistan relationship will take a Herculean effort," it says adding the incoming administration will bring in readiness to consider fresh approaches to deal with this important yet difficult relation.

Pakistan would remain central in US security strategy because of the country's nuclear arsenal; insurgency in tribal areas and parts of settled areas of NWFP; and the ongoing war in Afghanistan.

The report points out that because of these reasons the US cannot afford to see Pakistan fail.

Increasing support for civilian institutions in Pakistan has been proposed that could provide oversight of the military and premier intelligence agency, Inter-Services Intelligence (ISI).

Furthermore, it counseled the US to exercise patience with Pakistan and be modest in its expectations, while being prepared for a longterm effort.

But at the same time, it said, Pakistan needed to be told in most categorical terms that US patience was not unlimited, and that the US would be patient only so long as the Pakistan government is achieving visible results in its efforts against extremists in the tribal areas. (ANI)