March) and the Briand government fell (19 March). Confidence in Nivelle's planned offensive did not improve when Paul Painlevé was appointed to become the French Minister of War, as Painlevé had little faith in Nivelle's concepts. The British CIGS "Wully" Robertson described Nivelle as a commander "with a rope round his neck". Philippe Pétain, over whose head Nivelle had been promoted to become commander-in-chief, wanted to launch a major attack against the Germans near Reims. The proposal is considered to have likely resulted in considerable difficulties for the Germans, but Nivelle refused because Petain's offensive would delay Nivelle's offensive for two weeks. General Micheler, commander of the French Reserve Army Group, which was to exploit the expected breakthrough on the Aisne, had serious misgivings about the upcoming battle. In a letter to Nivelle on 22 March, Micheler argued that the French might not break through as quickly as Nivelle wanted, as the Germans had reserves available, and had strengthened their defenses along a key sector of the Aisne. The other commanders of the French army groups also had concerns, but Nivelle did not make any major adjustments to his plan. Assisted by Colonel (and former Minister of War) Adolphe Messimy, Micheler communicated his worries to Prime Minister Alexandre Ribot. On 6 April, Nivelle met with Micheler, Pétain and several politicians, including President Poincaré and Minister of War Painlevé at Compiegne. The investigation made the mistake of questioning Nivelle's subordinates - the Army Group Commanders - in front of him. Painlevé argued that the Russian Revolution meant that France shouldn't expect any major help from Russia, and that the offensive should be delayed until American forces were available and could get involved. Micheler and Petain said that they doubted the French force allocated to the attack could penetrate beyond the second line of the German defences, and suggested a more limited operation. Poincaré, summing up the discussions, said that the offensive should proceed, but that it should be halted if it failed to rupture the German front. At this point, Nivelle threatened to resign if his plan was not accepted but the politicians declared their complete confidence in him. Thus Nivelle's plan went unchanged despite the doubts expressed by the other generals and he was under greater pressure to achieve decisive results. Prime Minister Ribot said, "Our hand has been forced: It is too late to go back". On 4 April,