India, May 9 — After more than a year of doling out carrots to Pakistan, the Obama administration has reminded its strategic partner on the Afghanistan border that the US mood could quickly sour if FBI investigators confirm ties between the Times Square bombing suspect and Pakistani insurgent groups.

The warnings so far have been nonspecific, and publicly couched in confidence that the Pakistanis will do whatever is required. But the administration has indicated that anything less than full cooperation on the May 8 bombing attempt could make the continued flow of billions of US economic and security dollars “problematic,” officials from both countries said.

Pakistani efforts to combat the militants have under gone a positive “sea change” over the past year, Secretary of State Hillary Rodham Clinton said in an interview to be broadcast Sunday on CBS’s “60 Minutes.” But “we want more, we expect more,” Clinton said.

“We’ve made it very clear that if, heaven forbid, an attack like this that we can trace back to Pakistan were to have been successful, there would be very severe consequences.” Gen Stanley McChrystal, the US commander in Afghanistan, gave a similar message on Friday during a meeting with Pakistani Army Chief of Staff Gen. Ashfaq Kiyani.

On Saturday, the administration delivered a formal request to Pakistan for assistance in investigating the suspect’s ties with militants in Pakistan’s tribal regions. An ever-closer relationship with Pakistan is at the core of Obama’s war strategy in Afghanistan and against Al-Qaida. The nature and outcome of the threatened consequences for noncooperation are subjects the administration has barely begun to contemplate.

“There’s going to be enough here to trigger a policy debate,” predicted one senior official with access to US intelligence on Pakistan and involvement in White House discussions about the bombing attempt. “This is going to really create a new focus on Pakistan, militants in the tribal areas and their recruitment of and connections” to terror operatives recruited in the West, the official said.

Like others who agreed to discuss sensitive US-Pakistan relations and the ongoing bomb investigation, this official would speak only on the condition of anonymity. The suspect, Pakistan-born and raised Faisal Shahzad, is a naturalised US citizen who has told investigators that he was trained and directed by Tehrik-e-Taliban, the so-called Pakistani Taliban, and met with its highest officials during recent visits there.

The hapless nature of the plot, and Shahzad’s his willingness to talk about it freely, have led officials to question some aspects of his account. But his story and other evidence have provided more than enough signposts leading back to Pakistan. To some US officials, Shahzad’s story has exposed a growing disconnect between the long-term strategy of patiently wooing Pakistan, and the reality of an increasingly direct threat to the US homeland from Pakistani-based militants.

Impatient with the intricacies of Pakistani politics, its anti-American sensitivities and its fixation on India as its greatest strategic threat, these officials see the Times Square incident as weighing in favor of a far more muscular and unilateral US policy. It would include a geographically expanded use of drone missile attacks in Pakistan and pressure for a stronger US military presence there.

To others, however, it is too early to draw firm conclusions about Shahzad’s connections and how the Pakistani government will deal with them. For now, the operative administration view is that expanded US aid and strategic ties have begun to pay dividends and “reinforce the point that the strategy we designed over a year ago was the right strategy,” one official said. If the bomb attempt had happened early in the administration, he and others said, cooperation would have been tenuous at best.

Asked whether any change in strategy was currently being contemplated, a senior US military official responded, “The answer is no.” These officials point out their confidence is not based solely on trust. Pakistan’s economy is on the verge of collapse, with gross domestic product falling from more than 8 per cent growth in 2005 to under 3 per cent last year.

More than $3.5 billion in US economic and military assistance is in the pipeline, and a nearly $8 billion International Monetary Fund agreement and $3.5 billion World Bank financing package are pending. In economic terms, one Pakistani official said, “the cumulative impact of the US role is enormous.”

Insurgent groups with sanctuaries or operations in Pakistan range from Al-Qaida and the Afghan Taliban networks to domestic organisations including the Pakistani Taliban and Kashmir-focused groups such as Jaish-e-Mohammed and Lashkar-e-Taiba. The administration has argued that they increasingly overlap and urged Pakistan to take them all on.

In response, Pakistan has discounted a significant Al-Qaida presence, and been slow to break its long-standing intelligence ties with the Afghan Taliban leaders it sees as a hedge against an unfriendly government next door. Far from taking on the Kashmiri groups, it has considered them a strategic asset against its traditional Indian adversary.

Following a series of domestic attacks and suicide bombings, it has conducted fierce and costly offensives over the past year against the Pakistani Taliban in the Afghan border badlands of the northwest frontier and the Federally Administered Tribal Areas, or FATA.

The United States has contributed by targeting Pakistani Taliban leaders with drone strikes, and praised the Pakistani military as it drove Taliban forces from their operational base in the FATA region of South Waziristan. But that patience, administration officials warned, does not extend to the Shahzad case.