President Vladimir Putin on Friday brushed off a lightning Ukrainian counter-offensive with a smile but warned that Russia would respond more forcefully if its troops were put under further pressure.

Speaking after a summit of the Shanghai Cooperation Organisation in the Uzbek city of Samarkand, Putin cast the invasion as a necessary step to prevent what he said was a Western plot to break Russia apart. Moscow, he said, was in no hurry in Ukraine. And its goals remained unchanged.

“The Kyiv authorities announced that they have launched and are conducting an active counter-offensive operation. Well, let’s see how it develops, how it ends up,” Putin said with a grin.

It was his first public comment on a rout of his forces in northeastern Ukraine’s Kharkiv region a week ago that has prompted unusually strong public criticism. Russia hit Ukrainian infrastructure in response — including a reservoir dam and electricity supplies — and Putin said those attacks could get worse.

“Recently, the Russian armed forces have inflicted a couple of sensitive blows. Let’s assume they’re a warning. If the situation continues to develop like this, then the response will be more serious,” he said.

Putin also said Russia was gradually taking control of new areas of Ukraine.