Small teams of US special forces soldiers have been secretly embedded with Pakistani military forces in the tribal belt, helping to hunt down Taliban and al-Qaida fighters and co-ordinate drone strikes, the embassy cables reveal.

The numbers involved are small – just 16 soldiers in October 2009 – but the deployment is of immense political significance, described in a cable that provides an unprecedented glimpse into covert American operations in the world's most violent al-Qaida hotbed.

The first special forces team of four soldiers was deployed to an old British colonial fort in the northern half of the tribal belt in September 2009, helping Frontier Corps paramilitaries to carry out artillery strikes on a militant base.

A month later, two more teams of six soldiers each were deployed to Pakistani army bases in North and South Waziristan, a lawless warren of mountains considered to be the global headquarters of al-Qaida.

Their job was to provide "intelligence, surveillance and reconnaissance" support – ISR in military jargon – "general operational advice" and to help set up a live satellite feed from American drones flying overhead, presumably CIA-operated Predator and Reaper aircraft.

American officials, who had long been pushing for such a deployment in the face of "adamant" Pakistani opposition, were jubilant, viewing it as a sign of growing trust in an often troubled relationship.

"The developments of the past two months thus appear to represent a sea change in [the military's] thinking," read the cable.

American special forces had been deployed in Pakistan since 2008 but were limited to a training role, it noted. Permission for the active combat deployment "almost certainly" came with the personal consent of the army chief, General Ashfaq Kayani.

"Patient relationship-building with the military is the key factor that has brought us to this point. The Pakistanis are increasingly confident that we do not have ulterior motives in assisting their operations."

The participation of American soldiers in combat operations in the tribal campaign has never been publicly acknowledged due to its extreme political sensitivity in a country seething with anti-US sentiment.

Only a year earlier, Pakistan generals issued thinly veiled threats against the US after President George Bush authorised a crossborder special forces raid on a militant hide-out in Waziristan that provoked a wave of outrage across Pakistan.

The deployment of special forces soldiers to the tribal belt in 2009 coincided with a dramatic surge in drone strikes in the same areas. On 8 December, the al-Qaida leader Saleh al-Somali was killed in a missile strike close to Miram Shah in North Waziristan.

Between 400 and 700 people died in drone strikes in 2009, according to a count by the New America institute. The proportion of civilian deaths remains a point of contention with critics who claim the strikes are stoking militancy, not ending it.

Pakistan's army is not the only arm of government quietly acquiescing with the programme, however. While government officials have slammed many strikes as a breach of sovereignty, the cables portray them quietly supporting the programme.

In August 2008, the interior adviser Rehman Malik advised the US to "hold off alleged Predator attacks until after the Bajaur operation", according to one cable.

The prime minister, Yousaf Raza Gilani, was more categorical. At the same meeting he said: "I don't care if they do it as long as they get the right people. We'll protest in the National Assembly and then ignore it."

Bureaucrats are also shown supporting the drones, viewing them as a solution to a problem – the Taliban's grip over the tribal belt – that numerous army operations had failed to resolve.

Speaking in an "unofficial capacity" last year, a senior tribal area official in Peshawar told US officials that "he and many others could accept Predator strikes as they were surgical and clearly hitting high value targets".

Most local people did not fear the strikes because "everyone knew that they only hit the house or location of very bad people", he said. "Our house is on fire and we need to take drastic actions."

The official, who holds a senior position in the governance of the tribal belt and whose name has been withheld by the Guardian, appeared to be speaking out of desperation.

The Taliban were rampaging across North-West Frontier Province (now Khyber Pakhtunkhwa), he said, and if the government failed to stop them then the militants could take over entirely – forcing him to ask them for a job.

"The taliban [sic] could capture the NWFP but they don't know how to administer it so they might need administrators like me," he is quoted as saying. "I might have to join the taliban at some point to just survive."