Qatar is finalising a deal to buy Russian S-400 air defence systems, the Gulf state's ambassador to Moscow announced on 25 January.

Fahad bin Mohammed Al-Attiyah, Qatar's ambassador extraordinary and plenipotentiary to Russia, said:  ‘Negotiations in this direction are in an advanced stage.’

Talks were also ongoing for the purchase of ‘ground force technologies,’ he added.

The announcement came after the visit of Saudi Arabia's King Salman to Moscow in 2017, when Riyadh signed preliminary agreements to buy the Almaz-Antey S-400 Triumf air defence systems and anti-tank guided missile systems.

Led by Saudi Arabia, the UAE, Bahrain and Egypt cut ties with Qatar in June 2017 over Doha's alleged ties to Islamist extremists and Shiite Iran.

Qatar denies the charges. It has stepped up diplomatic and trade efforts elsewhere in a bid to counter its regional isolation.

In December 2017, Russia announced it had completed negotiations with Turkey for the sale of an S-400 air defence missile system, raising eyebrows among Turkey's NATO partners.