The measure aimed to disrupt communications between Chechen field commanders and could signal a new federal push on Chechen fighters, the agency said, citing top Russian military sources. An AFP reporter in Ingushetia republic said his mobile telephone had ceased functioning, and telecoms officials said links had been cut in Dagestan and North Ossetia. News of the electronic warfare came as Russian forces sought to cut off escape routes from the beleaguered Chechen capital, Grozny, concentrating their fire on the town of Urus-Martan, 20 km southwest. Russian forces also shelled the Chechen capital and were moving in on Shali, around 20 km southeast. The onslaught has gained momentum in the past week with a string of towns, including the second city, Gudermes, opening their gates to Russian forces rather than face a punishing blitz. Russian commanders have given themselves a week to seize Urus-Martan, which would give them a stranglehold on the breakaway republic and hugely hinder supplies into Grozny.

Moscow claims the capital is already 80 per cent surrounded and is anxious to finish the circle by mid-December and force the government of Chechen President Aslan Maskhadov to surrender.