The Taliban on Tuesday vowed to continue fighting against US forces in Afghanistan after President Donald Trump said talks with the insurgents were "dead," saying Washington would regret abandoning negotiations.

The renewed war of words between the two sides raised the specter of violence in Afghanistan as Trump and the Taliban pledged to take the fight to each other following the precipitous collapse in talks.

"We had two ways to end occupation in Afghanistan: One was jihad and fighting, the ­other was talks and negotiations," Taliban spokesman Zabihullah Mujahid told AFP.

"If Trump wants to stop talks, we will take the first way and they will soon regret it."

The Taliban's statement came hours after Trump told reporters that the US was walking away from negotiations after nearly a year of talks that aimed to pave the way for an American withdrawal from Afghanistan following 18 years of war.

"They are dead. As far as I am concerned, they are dead," Trump said at the White House.

The announcement followed Trump's dramatic cancelation of a top-secret plan to fly ­Taliban leaders in for direct talks at the Camp David presidential facility outside Washington.

Driving another nail into the coffin of what had appeared to be nearly finalized negotiations, Trump said a US military onslaught on the guerrillas was at its fiercest level in a decade.

"Over the last four days, we have been hitting our Enemy harder than at any time in the last ten years!" he wrote in a tweet.

On Sunday, Secretary of State Mike Pompeo said that "we've killed over 1,000 Taliban in just the last 10 days."

Trump angrily denied that the whiplash effect of his sudden shifts on Afghanistan was causing turmoil.

Until this weekend, there had been steadily mounting expectations of a deal that would see the US draw down troop levels in Afghanistan. 

In return, the Taliban would offer security guarantees to keep extremist groups out.

But then on Saturday, Trump revealed that he had canceled an unprecedented meeting between the Taliban and himself at storied Camp David.

He said this was in retaliation for the killing of a US soldier by the Taliban in a huge Kabul bomb blast last week.

The cancelation - announced on Twitter - was the first time most Americans learned that such a dramatic meeting was even planned.

Many in Washington were shocked and some were angry that the Taliban had been about to visit the presidential retreat on the eve of the anniversary of the September 11 terrorist attacks.