Ukrainian forces smashed across the Russian border on August 6 and grabbed a slice of land inside Russia in a bid to distract Moscow's forces from the front lines in eastern Ukraine and to gain a potential bargaining chip.
But a lightning Russian advance over the past few days has left Ukraine with a sliver of less than 200sq km in Kursk, down from 1300sq km at the peak of the incursion last summer, according to the Russian military.
"Our task in the near future, in the shortest possible timeframe, is to decisively defeat the enemy entrenched in the Kursk region," Putin told generals in remarks televised late on Wednesday.
"And of course, we need to think about creating a security zone along the state border."
The remarks by Putin, dressed in a green camouflage uniform, came as US President Donald Trump said he hoped Moscow would agree to a ceasefire and said that if not then Washington could cause Russia financial pain.
Valery Gerasimov, the chief of Russia's General Staff, told Putin that Russian forces had pushed Ukrainian forces out of over 86% of the territory they had once held in Kursk, the equivalent to 1100sq km of land.
Gerasimov said Ukraine's plans to use Kursk as a bargaining chip in possible future negotiations with Russia had failed and its gambit that its Kursk operation would force Russia to divert troops from its advance in eastern Ukraine had also not worked.
He said Russian forces had retaken 24 settlements and 259sq km of land from Ukrainian forces in the last five days along with over 400 prisoners.
Russia's operation to eject Ukrainian forces from Kursk has entered its final stage, state news agency TASS reported on Thursday citing Kremlin spokesman Dmitry Peskov.
Ukraine's top army commander, Oleksandr Syrskyi, said on Wednesday that Kyiv's troops will keep operating in Kursk as long as needed and that fighting continued in and around the town of Sudzha.
The US on Tuesday agreed to resume weapons supplies and intelligence sharing with Ukraine after Kyiv said at talks in Saudi Arabia that it was ready to support a ceasefire proposal.
The Kremlin on Wednesday said it was carefully studying the results of that meeting and awaited details from the US.
