ROME, Italy (AFP)— The European Union's coronavirus vaccination campaign should be able to inoculate "all those who need" by the end of summer or perhaps sooner, an EU official pledged on Thursday.

EU Industry Commissioner Thierry Breton said he was confident that "by the end of the summer, and I hope even sooner, all those who need to be vaccinated will have been".

The EU has faced sharp criticism over delays in vaccine rollouts, partly due to production bottlenecks, while other countries like Israel, Britain and the United States have been much faster.

Speaking in Rome after talks with Italian Economic Development Minister Giancarlo Giorgetti, Breton said he was "very impressed" by how pharmaceutical companies had managed to accelerate vaccine production.

"The issue is no longer about (having enough) vaccines, in Europe we have plenty of vaccines available," said the French EU official, a former businessman.

In a Wednesday interview with Italy's Corriere della Sera daily, Breton said EU countries have received 43 million doses, but have not yet used about 30 per cent of them.

According to the commissioner, by the end of the year the EU will be able to manufacture 2-3 billion vaccine doses per year, beating the production capacity of the US, China and Russia.

The commissioner called for EU unity, after several members of the bloc, including Slovakia, Hungary, Denmark and Austria, broke ranks to source vaccines from Israel, China or Russia.

"No single country can have an autonomous vaccination strategy ... we all depend on one another," Breton said.