India, April 24 -- The flow of Russian oil to Slovakia through the Druzhba pipeline that crosses Ukraine has resumed, Slovak Economy Minister Denisa Sakova said on Thursday, a breakthrough in an issue that has caused a major diplomatic spat in Europe.

The development is expected to unblock a large financial assistance package for war-ravaged Ukraine.

Populist Slovak Prime Minister Robert Fico welcomed the development, calling it "good news."

"Let's hope a serious relation between Ukraine and the European Union has been established," Fico said. He thanked all those involved in solving the issue, including the European Commission and Hungary.

Hungary and Slovakia were locked in a feud with Ukraine since Russian oil deliveries to Hungary...