Arthur Cox LLP, which is known to have advised on Russian LPN, ECP and securitisation structures, said on Friday that the invasion had prompted a review of all existing and any new Russia-related work.

“At this time, we have decided to both decline new instructions and cease all Russia-related work that goes against our values or existing or emerging sanctions,” the firm said in a short statement.

“Though we are subject to strict client confidentiality rules and are not at liberty to comment on individual clients, we can confirm that this review has already resulted in our ceasing to act for a number of clients.”

In a similar statement, Matheson said it is “deeply disturbed by, and strongly condemns, the unjustified attack by Russian forces on the people of Ukraine and on the sovereignty, democratic values and territorial integrity of Ukraine”.

The firm added: “Matheson has robust procedures in place to ensure the firm complies with all laws and regulations, including sanctions. We have therefore taken the decision not to accept instructions from Russian clients. We will continue to abide by all relevant international sanctions.”

Mason Hayes & Curran LLP (MHC) said it would no longer represent Russian clients who are “in any way aligned with the Russian state” or those who “may be contributing to the war effort”, confirming that this means it is resigning as lawyers to certain clients.

MHC managing partner Declan Black said: “We encourage the legal and business community to take similar steps and to go beyond sanctions.”

A&L Goodbody LLP said it carries out “very little direct work for Russian entities” as a result of its “stringent work acceptance criteria for high-risk countries like Russia”, but confirmed it is now “terminating the handful of mandates that we currently have, regardless of whether they are subject to sanctions or not”.

International law firms with bases in Ireland, such as DLA Piper, which also has an office in Moscow, have announced reviews of Russia-based work to ensure compliance with western sanctions.

Magic circle firm Linklaters, with established an Irish office less than a year ago, said it would shut its Moscow office and wind down all of its Russian operations in response to the invasion.

Linklaters said it would “continue supporting our people [in Moscow] in the process, doing all we can to help them transfer to new roles within Linklaters or otherwise”.