Pakistan's continued support for resurgent militant groups hostile to the United States, coupled with warming US military and business relations with India, is sharply diminishing Islamabad's strategic importance as an ally to Washington, US military, diplomatic, and intelligence officials and outside experts said.
According to a Reuters report, the United States has cut both military and economic aid to Pakistan sharply in recent years, reflecting mounting frustration among a growing number of officials with the nuclear-armed country's support for the Taliban in neighbouring Afghanistan.
That frustration has dogged US-Pakistan ties for more than a decade, but has spiked anew as the militant Islamic group has advanced in parts of Afghanistan that US and allied forces once helped to secure, the report citing US officials and analysts says.
"We're seeing a very definitive and very sharp reorienting of US policy in South Asia away from Afghanistan-Pakistan and more towards India," said Michael Kugelman, a South Asia expert with the Woodrow Wilson Center, a Washington think-tank.
The US relationship with Pakistan has long been a transactional one marked by mutual mistrust, marriages of convenience, and mood swings.
The long-standing US frustration with Pakistan's refusal to stop supporting the Taliban, especially within the US military and intelligence community, is now overriding President Barack Obama's administration's desire to avoid renewed military involvement in Afghanistan, as well as concerns that China could capitalize on fraying ties between Washington and Islamabad, the U.S. officials said.
Obama announced last month he would keep US troop levels in Afghanistan at 8,400 through the end of his administration, shelving plans to cut the force in half by year end.
American civilian and military aid to Pakistan, once the third-largest recipient of US foreign assistance, is expected to total less than $1 billion in 2016, down from a recent peak of more than $3.5 billion in 2011, according to US government data. The United States has not appropriated less than $1 billion to Pakistan since at least 2007.
The decrease also comes amid budget constraints and shifting global priorities for the United States, including fighting ISIS militants, a resurgent Russia and an increasingly assertive China.
In March, Republican Senator Bob Corker, chairman of the Senate Foreign Relations Committee, said he would seek to bar $430 million in US funding for Islamabad's purchase of $700 million of Lockheed Martin Corp. F-16 fighter jets (See: US lawmakers again slam F-16 sale to Pakistan). Earlier this month, secretary of defence Ash Carter refused to authorise $300 million in military reimbursements to Pakistan, citing the limited gains the country has made fighting the militant Haqqani network, which is based in the country's tribal areas bordering Afghanistan. The approval of such funding has been mostly routine in the past.
The US Congress has yet to authorise hundreds of millions of dollars in aid to Pakistan for the next fiscal year. The Pentagon is due to authorise $350 million in military aid for the next fiscal year, and cs unlikely to approve it under the Obama administration, a US defence official said, speaking on the condition of anonymity.
"Congress is no longer willing to fund a state that supports the Afghan Taliban, which is killing American soldiers," said Bruce Riedel, a Brookings Institution expert and former CIA officer who headed Obama's first Afghanistan policy review. In a stark illustration of the limits of US-Pakistan cooperation, the United States killed Taliban leader Mullah Akhtar Mansour in a drone strike in Pakistan's remote Baluchistan region in May, without informing Pakistan.
Some US officials still warn of the dangers of allowing relations with Pakistan to deteriorate. In a July 26 opinion piece in the Financial Times, Senator John McCain, chairman of the Senate Armed Services Committee, argued that "the strategic imperative for improved relations between the US and Pakistan is clear - for the safety of American troops and the success of their mission in Afghanistan, for the stability of the region and for the national security of both Pakistan and the US."
A senior Pakistani defence official said the United States will continue to need Pakistan in the fight against terrorism. Authorities in Islamabad have long rejected accusations that Pakistan has provided support and sanctuary to militants operating in Afghanistan.
"We have lost over a hundred billion dollars in fighting terrorism, which is more than anything they have given us," said the official, speaking on condition of anonymity.
In any event, the official said, Pakistan can turn to other sources of aid, including China. Last year the two countries launched a plan for energy and infrastructure projects in Pakistan worth $46 billion.
Nevertheless, the US tilt toward India, Pakistan's arch-foe, is likely to continue.
US defence companies including Lockheed Martin and Boeing Co are entering the Indian market, and the country has become the world's second-largest arms buyer after Saudi Arabia, according to data compiled by the Stockholm International Peace Research Institute.
Earlier this year, India and the United States agreed in principle to share military logistics, as both sides seek to counter the growing maritime assertiveness of China.