The latest negotiations between the two sides come as pressure builds for some sort of breakthrough in Afghanistan's gruelling conflict, with Washington jostling for a resolution.

Taliban spokesman Zabiullah Mujahid said the "sixth round of talks between (the Taliban) and the US will start in Doha today". The US embassy in Kabul confirmed the talks "are occurring".

US peace envoy Zalmay Khalilzad, a former US ambassador to Afghanistan, tweeted that he was in Doha and had met with the Indonesian foreign minister, who offered support for the talks.

The Afghan-born US envoy has spent several months shuttling between Asian capitals and Washington in a bid to build consensus for a deal.

On Sunday, he said Washington was "a bit impatient" to end the war, given its $45 billion annual cost to the US taxpayer and the continued toll on US forces, some 2,400 of whom have been killed since the US-led invasion in response to the September 11, 2001 attacks.

US President Donald Trump provided additional momentum when in December he told advisors he wanted to pull about half of America's 14,000 troops from Afghanistan.

- Mega meeting in Kabul -

Khalilzad has repeatedly stressed "there is no final agreement until everything is agreed" but the basic framework for a deal would see the US agree to pull its forces from Afghanistan in return for the Taliban vowing to stop terror groups ever again using the country as a safe haven.

None of the talks thus far have included the Afghan government, which the Taliban views as a puppet regime.

That means that even if the US and the Taliban can agree a deal to end the war and a timetable for an eventual troop withdrawal, the insurgents must still forge some kind of accord with Afghan politicians and tribal elders before an enduring ceasefire could kick in.

An initial attempt for an "intra-Afghan dialogue" -- due to take place last month in Doha -- collapsed in disarray at the last minute amid bickering over the lengthy list of delegates Afghan President Ashraf Ghani wanted to send.

Separately, thousands of Afghan politicians and representatives from various groups are meeting in Kabul this week at a "loya jirga" peace summit to discuss conditions under which they might envision some sort of deal with the Taliban.

Among top concerns are that the militant Islamist extremists would try to undo advances in women's rights, media freedoms and legal protections.

Mohammad Omar Daudzai, Ghani's special envoy for peace, welcomed the fresh US-Taliban talks and described how the jirga could feed into overall peace talks.

"The jirga sets a logical beginning for the peace process," Daudzai told reporters. "The people in the jirga will decide and set boundaries and the framework of talks."

Khalilzad went to Moscow last week, where Russia and China voiced support for the US plan for a peace deal and stressed the need for intra-Afghan dialogue that would see all sides in Afghanistan at a negotiating table.

Violence across Afghanistan meanwhile continues apace, and the Taliban last month announced the start of their annual spring offensive.