The US on Wednesday appointed an envoy to defend the rights of Afghan women, signalling a key priority as the Taliban ratchet up restrictions.

Rina Amiri, an Afghan-born US scholar and mediation expert who served at the State Department under former president Barack Obama, will take the role of special envoy for Afghan women, girls and human rights, State Secretary Antony Blinken announced.

Months after the US ended its 20-year war in Afghanistan, Blinken said that Amiri will address issues of “critical importance to me” and the rest of US President Joe Biden's administration.

“We desire a peaceful, stable and secure Afghanistan, where all Afghans can live and thrive in political, economic and social inclusivity,” Blinken said in a statement.

In a tweet, he added that Amiri brings "over two decades of expertise and specialised knowledge that will advance our vital work toward a more peaceful, stable, and secure Afghanistan for all".

The Taliban imposed strict Sharia law during their 1996-2001 regime, including banning women from working and girls from education.

Despite Taliban pledges to act differently after their August takeover, many women remain barred from returning to work and girls are largely cut off from secondary schooling.

On Sunday, the Taliban said that women would not be allowed to travel long distances without a male escort and that vehicle owners should not give rides to women unless they wear headscarves.