The EU insisted Thursday that any vaccine against coronavirus must be available fairly to all countries after French drug giant Sanofi said it was reserving first shipments for the US.

"The vaccine against COVID-19 should be a global public good and its access needs to be equitable and universal," European Commission spokesman Stefan de Keersmaecker told reporters.

Sanofi's chief executive Paul Hudson caused fury in France by announcing that US patients would get first access to a vaccine because Washington is helping to fund the research.

Ministers in President Emmanuel Macron's government slammed the move by Sanofi -- a French company -- as "unacceptable".

The EU organised a global fundraising effort this month for vaccine research which won around $8 billion -- but Washington pointedly refused to take part.

"For us in one word it is very important that, as the virus is a global virus, that we work on this globally," EU spokesman de Keersmaecker said.

The European Medicines Agency said Thursday that a vaccine might perhaps be ready in a year's time, but dubbed this an "optimistic" scenario.