Media playback is unsupported on your device Media caption The BBC's Orla Guerin says these much-needed supplies could soon be on the move again, following a long-awaited "sorry" from the US

Pakistan will reopen crucial supply routes to Nato-led forces in Afghanistan after the US apologised for killing 24 of its soldiers in November, Washington and Islamabad have said.

US Secretary of State Hillary Clinton said: "We are sorry for the losses suffered by the Pakistani military."

The Pakistani Taliban promptly threatened to attack the convoys.

The routes are increasingly important as Nato prepares to withdraw all combat troops from Afghanistan in 2014.

The row over the supply lines has been hugely damaging to relations between Pakistan and the US.

Transit fees

The dispute began in November last year when two dozen Pakistani soldiers were killed as US air strikes hit two posts on the Afghan border.

Analysis There were several surprises on how Nato supply routes were reopened through Pakistan on Tuesday. The Americans finally said sorry for the 26 November attack, and Pakistan decided to forego the transit fees and other benefits they were demanding. More surprisingly, the announcement came first from the US. It appears Pakistan needed a face-saver to avoid falling deeper into international isolation. Its powerful military, seen as the prime mover behind the Nato blockade, shared in the decision to open routes with the politicians. But this seven-month standoff has clearly shown the pitfalls in the US-Pakistan relationship. The Americans will continue to feel the need to keep Pakistan's influence in Afghanistan at a minimum, and will remain wary of Islamabad's tendency to whip up anti-Americanism at home to achieve regional objectives.

At the time, Afghan officials said that Nato forces had been retaliating for gunfire from the Pakistani side of the volatile border, but Pakistan rejected that claim.

Mrs Clinton made the announcement in Washington after talks by phone with her Pakistani counterpart, Hina Rabbani Khar.

"I offered our sincere condolences to the families of the Pakistani soldiers who lost their lives," she said in the statement .

"Foreign Minister Khar and I acknowledged the mistakes that resulted in the loss of Pakistani military lives.

"We are sorry for the losses suffered by the Pakistani military. We are committed to working closely with Pakistan and Afghanistan to prevent this from ever happening again."

Islamabad confirmed it would not raise transit fees when the lines re-open.

US officials say the existing charge of $250 (£160) per truck will not change - Washington had baulked at a Pakistani demand for $5,000 per container to let supplies flow again.

The BBC's Kim Ghattas says Washington had resisted saying sorry as there is deep anger among Americans about the death of US soldiers in Afghanistan from attacks by militant groups with alleged connections to Pakistan's ISI intelligence agency.

Media playback is unsupported on your device Media caption Nato has 100,000 personnel in Afghanistan. How will it get them out?

Shortly before Tuesday's announcement, Pakistani Prime Minister Raja Pervez Ashraf said the issue had damaged his country's relations with the US, as well as the 28 other Nato member states.

During the dispute the US reduced its reliance on Pakistan by using a more costly route through Central Asia.

US Defence Secretary Leon Panetta welcomed Pakistan's decision on Tuesday.

US-Pakistan: Uneasy allies 30 Sept 2010: Nato helicopters kill two Pakistani soldiers - border closure follows

Nato helicopters kill two Pakistani soldiers - border closure follows 22 April 2011: Supplies to Nato in Afghanistan halted for three days in protest over drone attacks

Supplies to Nato in Afghanistan halted for three days in protest over drone attacks 2 May: US announces Bin Laden's death and says Pakistan not warned of raid

US announces Bin Laden's death and says Pakistan not warned of raid 26 Nov: Nato air strikes on checkpoints on Afghan border kill 24 Pakistani troops

Nato air strikes on checkpoints on Afghan border kill 24 Pakistani troops 27 Nov: Pakistan closes Nato supply routes to Afghanistan

Pakistan closes Nato supply routes to Afghanistan 12 Dec: Pakistan's prime minister says neither country trusts the other

Pakistan's prime minister says neither country trusts the other Jan-Jun 2012: Drone strikes kill dozens of militants on the Afghan/Pakistan border, with a brief hiatus during April

Drone strikes kill dozens of militants on the Afghan/Pakistan border, with a brief hiatus during April 3 July: US confirms supply routes are to be reopened after apologising to Pakistan for troop deaths

"We remain committed to improving our partnership with Pakistan and to working closely together as our two nations confront common security challenges in the region," he said in a statement.

General John Allen, the US commander of Nato troops in Afghanistan, said the decision to open the supply lines was "a demonstration of Pakistan's desire to help secure a brighter future for both Afghanistan and the region at large".

Gen Allen had held talks in Islamabad twice in the last six days.

In April, Pakistani lawmakers approved new guidelines for ties with the US, but demanded that the country provide an unconditional apology for the November attack, and stop drone strikes.

The standoff cast a diplomatic shadow over a Nato summit two months ago in Chicago where correspondents said US President Barack Obama snubbed his Pakistani counterpart, Asif Ali Zardari.

Relations between the US and Pakistan were severely strained for much of last year, reaching crisis levels following the killing of al-Qaeda leader Osama Bin Laden by US forces in Pakistan in May.