Shanahan will meet President Ashraf Ghani, whose government was not part of major talks between US and Taliban officials last month that negotiators hope could bring a breakthrough in the grinding 17-year conflict.

The US diplomat leading the talks has expressed hope at finding a deal before Afghan presidential elections scheduled for July, as President Donald Trump calls for an end to American military involvement in the war-torn country.

The Taliban consider the Kabul administration a US puppet but Ghani's allies in Washington insist Afghans should lead the peace process.

The months-long push by the US to engage the Taliban has ostensibly been aimed at convincing them to negotiate with Kabul.

The insurgents have also met with a high-ranking delegation of Afghan politicians-- including chief Ghani rivals -- in Moscow last week to discuss their role in the country's future and a possible path towards peace.