Russian President Vladimir Putin on Friday said Moscow would "respond" after a Ukrainian court placed the Kremlin chief's close ally under house arrest in a treason case. "Taking into account all the threats that are being created for us, we will have to respond to this properly and in a timely fashion," Putin said at a meeting of his security council, apparently referring to the prosecution of Viktor Medvedchuk, a Kremlin-friendly Ukrainian lawmaker. as/acl/ach