Russia launched a ground assault into Ukraine's northeast last week to stop cross-border shelling, but has no current plans to capture Kharkiv city, President Vladimir Putin said Friday.

Thousands of Russian troops stormed the border on May 10, unleashing artillery fire on several towns and villages and seizing over 200 square kilometres of land, their biggest advance in 18 months.

"As for what is happening on the Kharkiv front, this is their fault, because they have shelled and continue to shell residential neighbourhoods in border areas including Belgorod," Putin told reporters in the Chinese city of Harbin.

"And I said publicly that if this continues, we will be forced to create a security zone," he added.

Belgorod has been repeatedly targeted by deadly artillery and drone strikes that Moscow blames on Kyiv.

When asked about whether Russia planned to capture the city of Kharkiv, which has over a million inhabitants, Putin said: "As for Kharkiv, there are no such plans as of today."

He also said that he discussed the Ukraine conflict with Xi Jinping during their informal meeting earlier, and praised Beijing's efforts to end the conflict.

"We have repeatedly said, we believe that China is sincerely seeking to resolve this problem, offers various options, behaves very flexibly," Putin said.