The Russian president, Vladimir Putin, has appeared to concede the severity of the Kremlin’s recent military reversals in Ukraine, insisting Russia would “stabilise” the situation in four Ukrainian regions it illegally claimed as its own territory last week.

Russia has suffered significant losses in two of the four regions since Friday, when Putin signed treaties to incorporate them into Russia by force, with Russian officials saying their forces were “regrouping”.

“We are working on the assumption that the situation in the new territories will stabilise,” Putin told Russian teachers during a televised video call.

With Ukraine pushing its advance in the east and south, Russian troops have been retreating under pressure on both fronts, confronted by fast moving and agile Ukrainian forces supplied with advanced western-supplied artillery systems.