PARIS: The European Union shouldn't be the "useful idiot" of the COVID-19 pandemic by exporting vaccines while other countries keep supplies for themselves, a French official said on Wednesday, backing plans for tougher rules on vaccine exports.

"Europe shouldn't be a sort of useful idiot in the battle against the virus," the French presidential adviser told reporters ahead of a virtual EU summit on Thursday.

The European Commission will extend EU powers to potentially block COVID-19 vaccine exports to Britain and other areas with much higher vaccination rates, and to cover instances of companies backloading contracted supplies, EU officials have said.

The regulation is aimed at making vaccine trade reciprocal and proportional so that other vaccine-making countries sell to Europe and the EU does not export much more than it imports, one EU official said.

France will support this updated EU system, the French official said. "We have exported a lot (of vaccines), we've played by the rules. The same can't be said about some of our partners," he said.

The EU had no interest in entering some sort of "blame game" with Britain on vaccine exports, the official said, adding EU politicians had nothing to gain from the row in the eyes of their own public opinion.

"As far as we're concerned, we have no willingness, no interest in fuelling permanent controversy with Britain."