BioNTech could have capacity to make 3 billion doses of Covid-19 vaccine with US partner Pfizer next year, said the German company’s chief executive Ugur Sahin.

This aims at making their pioneering shot far more widely available around the world.

“In principle, we could further increase manufacturing capacity,” said Sahin on Tuesday in an interview with Bloomberg TV. “It depends on demand, and on factors such as if an additional boost to vaccinations is required.”

Demand is growing tremendously around the world for Covid vaccines as countries need to breathe back life into economies, return children to schools and get people back into offices and shops.

Both the US and Europe have sought to accelerate vaccine deliveries this year as new, more aggressive variants of the virus spread.

“We have an order book of already 1.3 billion orders, which is already fixed,” Sahin said. “We are discussing additional doses – hundreds of millions of doses as options – with government organizations.”

The two companies have committed to make 2 billion doses of their two-shot vaccine this year. Pfizer promised to ship two-thirds of the US’s 300 million-dose order by the end of May. In the European Union, the partners have promised to ship at least 500 million doses this year, with an option for an additional 100 million doses.

Pfizer has projected about $15 billion in revenue this year from Covid vaccine sales, and chief executive Albert Bourla said the price of the shot may increase.

Shin asked for continued solidarity among EU countries, despite concerns in countries like Germany that tethering vaccine purchasing and distribution to the bloc has slowed the immunization push.

In the UK, more than a third of the population has received a shot, compared with 6 percent in Germany, according to Bloomberg’s vaccination tracker.