In a message on its website, militant group Islamic State Khorasan Province (IS-K) on Monday claimed responsibility for the attack near the entrance of the Russian embassy in Afghan capital Kabul.

Two Russian embassy staff were among the six people killed when a suicide bomber detonated explosives near the embassy, the Russian Foreign Ministry and Afghan officials said on Monday.

Police said the attacker was shot dead by armed guards as he approached the gate, in one of the first such attacks since the Taliban took power last year.

The UN mission in Afghanistan has condemned the blast.

(With input from agencies)