President Mikhail Saakashvili of Georgia threatened a separatist leader in the west of the country with an economic blockade last night as tensions in the country rose dangerously. The threat came after militiamen loyal to Aslan Abashidze, who controls the region of Adjara, stopped a presidential convoy entering their territory by firing shots in the air. Mr Saakashvili responded by closing the country's air space and putting the national army on alert. He said last night that if Mr Abashidze did not allow him access today, he would blockade Adjara's airspace and oil port and seize the regional leadership's bank accounts. If neither side backs down, civil war could ensue. Witnesses reported that officials in Adjara were handing out guns and mining bridges in preparation for conflict. Russia, which supports Mr Abashidze, warned Mr Saakashvili not to use force to resolve the dispute. A Russian foreign ministry spokesman, Alexander Yakovenko, said: "In the event of a crisis, all responsibility would lie with the Georgian leadership." **PHOTO CAPTION*** Aslan Abashidze (L) and Mikhail Saakashvili.