BBC correspondent Paul Reynolds explains the Russian leader's concerns in Chechnya:
"His insistence that there can be no surrender to demands for independence for Chechnya is based on a number of factors which include:
* a fear of further chaos on Russia's borders in the region
* a feeling that Russia must not make any further territorial concessions anywhere
* a belief that the Chechens were offered and threw away the chance of responsible independence before.
"Mr Putin has also added into this complex mix the spectre of international (by which he means Islamic) terrorism and an accusation that unnamed foreign countries want to break bits off Russia. It must also not be forgotten that he has staked his own reputation on his policy and that therefore he is reluctant to change it."