KYIV, July 7 (Reuters) - Vladimir Putin on Thursday (Jul 7) accused the West of decades of aggression towards Moscow and warned that if it wanted to attempt to beat Russia on the battlefield it was welcome to try, but this would bring tragedy for Ukraine.

His remarks came as Russian Foreign Minister Sergei Lavrov prepared for a closed-door foreign minister's meeting at a G20 gathering in Indonesia on Friday which will be the first time Putin's top diplomat comes face-to-face with the most vocal opponents of the invasion of Ukraine in February.

In Ukraine, the regional governor of the northeastern city of Kharkiv said late on Thursday that three people had been killed and another five wounded after Russian forces shelled the city.

Russian forces also shelled other potential conquests in eastern Ukraine ahead of an expected new offensive.

"We have heard many times that the West wants to fight us to the last Ukrainian. This is a tragedy for the Ukrainian people, but it seems that everything is heading towards this," Putin said in televised remarks to parliamentary leaders.

The West had failed in its attempt to contain Russia, and its sanctions on Moscow had caused difficulties but "not on the scale intended", Putin added. Russia did not reject peace talks, but the further the conflict went, the harder it would be to reach agreement, he said.