This article is more than 3 years old

This article is more than 3 years old

Qatar sought to apply pressure to the four states laying siege to its economy on Sunday by saying it had set up a special committee to pursue multi-billion compensation claims against them.

The announcement by Qatar’s attorney general threatens to add a further costly legal dimension to the battle between Qatar and its rivals Saudi Arabia, United Arab Emirates, Bahrain and Egypt.

The four countries in dispute with Qatar have already themselves demanded compensation from Doha for what they allege was past interference in their internal affairs. The demand is one of 13 made by the quartet – part of a major power struggle that has torn apart the west’s key Gulf allies.

The Qatari attorney general said the compensation claims would be made on behalf of the businesses affected by the land and air embargo imposed by the four countries. The four insist they are mounting only a boycott and not a blockade. Qatar’s attorney general, Ali bin Fetais-al Marri, said he had set up a central committee to collate claims.

Qatar diplomatic crisis – what you need to know Read more

The US secretary of state, Rex Tillerson, will visit the region on Monday to see if he can add to the mediation work already being led by Kuwait.

The UK foreign secretary, Boris Johnson, spent the weekend shuttling between the major regional capitals urging both sides to de-escalate the dispute.

A decision is expected at the high court in London on Monday on whether the UK is in breach of its arms export licence laws for giving the go-ahead to the UK defence industry to sells arms to Saudi.

The Campaign against the Arms Trade has brought a judicial review claiming the UK government should have suspended arms sales on the basis there was a serious risk the Saudis would use the arms in the war in Yemen in breach of international humanitarian law.