Clifford Chance lawyers will make a final attempt this week to strike a deal for Western banks with the Russian central bank on how businesses and institutions there will repay billions of dollars in defaulted domestic debt.

The lawyers have until 17 November, when the 90-day debt moratorium imposed by the Russian government expires. If no deal is made, a raft of litigation is expected.

Clifford Chance partners Cliff Godfrey and Andrew Yianni are acting for a steering committee of major commercial banks owed £6.5bn.

Lawyers in other firms acting for individual banks are pessimistic. Jeff Roberts, partner at Freshfields' Moscow office, said: “The deadline is unlikely to be extended and the expectations of government and foreign investors are still too far apart.”