Cleverly said London valued the position of Astana - which has traditionally been closely allied with Moscow - on the Ukrainian conflict. Kazakhstan has refused to support Russia's invasion or recognise its annexation of Ukrainian territories.

"The UK greatly appreciates Kazakhstan's consistent and principled position in supporting Ukraine's territorial integrity and your desire to bring about resolution to the war in line with the UN charter," he told a briefing.

Cleverly, who met Kazakh President Kassym-Jomart Tokayev and a number of other senior officials, said he discussed the disruptions in Kazakh oil exports - most of which go through Russia - and discussed ways to support the development of alternative routes such as the so-called Middle Corridor.

That route crosses the Caspian Sea, Azerbaijan, Georgia and Turkey, and requires significant investment in order to boost its capacity, although Kazakhstan has already started diverting some crude shipments towards it.

Cleverly and Kazakh diplomats said they have signed a memorandum on critical minerals such as rare earth metals, but provided no details about it.

The landlocked former Soviet nation of 20 million accounts for almost a half of the world's uranium output and has large deposits of rare earth minerals which the West has traditionally sourced from China or Russia.

Kazakhstan, which has the longest land border with Russia of any former Soviet state, called in Russian troops to help put down street demonstrations weeks before Russia's invasion of Ukraine last year. But since the invasion Tokayev has been careful to keep his distance from Moscow and keep relations open with the West.