Although the siege was partially lifted soon afterwards and a successful sortie allowed a communication route between the city and the rest of Poland, a large Russian force remained on the left bank of the Vistula and continued to threaten the city. Russian commander Ivan Paskevich counted on Polish surrender as his Polish counterpart, Jan Krukowiecki, was known to be a member of the moderate political forces, willing to negotiate with Russian tsar Nicholas I, who had been deposed from the Polish throne in January 1831 by the Sejm (Polish parliament). When a less conciliatory faction gained power in Warsaw and the Russian offer of surrender was refused, Paskevich ordered his forces to launch an assault against Warsaw's western defences.