Afghanistan President Hamid Karzai has accused the United States of colluding with the Taliban to justify its presence in Afghanistan, dumbfounding US officials during a problematic visit by the new Pentagon chief.
A joint news conference by Karzai and US defence secretary Chuck Hagel was cancelled on Sunday, as the Afghan leader's allegations compounded the troubled nature of the visit after a security scare from twin bomb attacks on Saturday.
"The bombs that were detonated in Kabul and Khost were not a show of force, they were serving America," Karzai said in a televised speech, referring to the two suicide blasts in which 19 people were killed.
The president said the United States was in "daily" talks with the Taliban and that insurgent suicide attacks enabled the international military force to vindicate its deployment in Afghanistan.
"It is their slogan for 2014, scaring us that if the US is not here our people will be eliminated," he said, as US-led combat troops begin a long withdrawal after more than a decade of war.
Karzai, who has frequently lashed out at perceived US slights through inflammatory language, was angered by a new delay to the planned transfer of the controversial Bagram jail from US to Afghan control.
He is also adamant that his government must be involved in any US-Taliban contacts, although the Islamist militia dismisses him as a US puppet and says no dialogue has taken place with the Americans since a year ago.
Karzai insisted that in "Europe as well as in Gulf countries, the Taliban and the Americans and foreigners are in talks on a daily basis".
The president's news conference with Hagel was scrapped just a few hours before it was due to be held at the presidential palace in Kabul, with US officials citing unspecified security concerns.
The Pentagon chief, on his first official visit to Afghanistan after he endured a difficult confirmation process by the US Senate, tried to downplay tensions with Karzai after they met in private.
"He has his ways," Hagel said. "There will be new challenges, there will be new issues. It shouldn't come as a surprise... but I don't think any of these are challenges that we can't work (our) way through.
"I told the president that it was not true that the United States was unilaterally working with the Taliban," he added. "The fact is any prospect for peace or political settlements, that has to be led by the Afghans."
General Joseph Dunford, commander of the 100,000 NATO forces in Afghanistan, was blunter than his boss.
"I don't know why President Karzai might be doing this," he said. "I guess his perspective is maybe it's productive to air these differences in public... but I let others judge if that's being particularly helpful."
Hagel and Karzai's talks came as the two countries face up to a testing transition phase in which NATO-led troops exit Afghanistan and Afghan forces take on fighting the Taliban alone.
The United States and Afghanistan are also negotiating a strategic pact that will determine the US presence in Afghanistan after the end of the international combat mission.
Karzai raised another point of friction on Sunday by issuing a decree banning international forces from entering university grounds after alleged harassment of students.
Also troubling US-Afghan ties has been the long dispute over the fate of suspected militants held by US forces at Bagram jail.
A final handover scheduled on Saturday was delayed due to last-minute disagreements, officials from both sides said.
"There's probably a slight difference of perspective between us and the Afghans and we're working out that right now," Dunford admitted.
"Transitions are tough," he said. "Our relationship is changing, it's maturing, we're moving into support as they move into the lead and we're going to have to grind through issues as they occur."
Dunford denied the allegations of NATO harassment of students and declined to say when US special forces would leave Wardak province, despite a deadline set by Karzai two weeks ago that expired on Sunday.