Britain's foreign secretary has cancelled a landmark trip to Russia amid escalating tensions in Syria.

Boris Johnson was due to be the first British cabinet member to visit the Kremlin since 2012, after the Foreign and Commonwealth Office (FCO) made a sustained attempt to improve relations with Moscow.

He was due to meet his counterpart Sergei Lavrov next week, but Johnson confirmed the cancellation in a statement released on Saturday (8 April).

Johnson said: "Developments in Syria have changed the situation fundamentally.

"My priority is now to continue contact with the US and others in the run up to the G7 meeting, on 10 April and 11 April, to build co-ordinated international support for a ceasefire on the ground and an intensified political process.

"I will be working to arrange for other like-minded partners to meet and explore next steps soon too."

Johnson added he had discussed his intentions with US Secretary of State Rex Tillerson, who will still travel to Moscow after the G7 meeting as originally planned to deliver a "clear and co-ordinated message to the Russians".

"We deplore Russia's continued defence of the Assad regime even after the chemical weapons attack on innocent civilians," Johnson said. "We call on Russia to do everything possible to bring about a political settlement in Syria and work with the rest of the international community to ensure that the shocking events of the last week are never repeated."

Both the Russian and the Syrian governments have denied any involvement in the chemical gas attack.

The Organisation for the Prohibition of Chemical Weapons (OPCW) is investigating the attack but has yet to reach a conclusion. Syria is a member state of the OPCW.

Following the announcement of Johnson's cancelled visit, a spokeswoman of the Russian Foreign Ministry, Maria Zakharova, told state-controlled news agency TASS: "This cancellation of the visit followed its recent postponing. The UK side named various reasons.

"The impression is that our Western counterparts live in some special reality, where at first they are trying to make collective plans unilaterally, and then to have them changed also unilaterally, inventing absurd reasons."