Jens Spahn said it wasn’t clear whether the decision by the European Medicines Agency would explicitly recommend against using the vaccine in people 65 and over, or whether it would merely note the lack of data for older people, meaning “no restrictions but caution in certain areas.” Germany will adjust its own guidance once it sees the EMA’s decision.

“We don’t expect an unrestricted approval,” Spahn told reporters in Berlin. “The data available for older people, and that’s been the debate in recent days, isn’t sufficient for that.”

In a possible sign of last-minute discussion among experts, the regulator postponed the news conference at which the announcement was expected Friday afternoon by 90 minutes.

While the AstraZeneca vaccine has been authorized for all adults in other countries, only 12% of the participants in its research were over 55 and they were enrolled later, so there hasn’t been enough time to get results.

Also read: German draft doesn’t recommend AstraZeneca jab for over-65s

A large trial published last month showed the vaccine was about 70% effective in preventing people from getting sick from the coronavirus, although it is unknown whether the shot stops disease transmission.

A recommendation that only people under 65 get the vaccine could complicate the rollout in many European countries that have focused on giving shots to older people first at a time when they have been criticized for not vaccinating people as quickly as Britain, Israel and the U.S. The rollout difficulties are particularly worrying as countries face surging cases in a pandemic that has taken the lives of more than 400,000 people in the 27-nation bloc.

While politicians have blamed supply problems for the slow rollout, other factors, like onerous paperwork and poor planning, have also played a role. The EU has particularly lashed out at AstraZeneca after the drugmaker said it would supply less vaccine in a first batch than originally anticipated. Further raising concerns about supplies to the bloc, which is home to some 450 million people, Moderna told countries including Italy and Denmark the company would be delivering fewer vaccines than originally expected.

Spahn, the German health minister, said he understood many were waiting impatiently for the vaccine, but cautioned that “several hard weeks of vaccine shortage still lie before us.”

The EU bet heavily on the AstraZeneca shot, which is cheaper and easier to handle than some other vaccines, with orders for 300 million doses to be delivered after authorization and options for another 100 million doses.

On Thursday, a draft recommendation from Germany’s vaccination advisory committee said the AstraZeneca vaccine should only be given to people aged 18-64 for now. Britain’s medicines regulatory agency also acknowledged the limited data in older people but still cleared the shot last month for all adults, with some caution for pregnant women.

A separate study testing the AstraZeneca vaccine in the U.S. is still underway.

Julian Tang, a virologist at the University of Leicester, said he thought any recommendation to limit the vaccine’s use to people under 65 was understandable, but “overly cautious.”

Also read: Germany, Hungary give 1st vaccine shots ahead of EU rollout

He said that although data on the vaccine’s effectiveness in older populations was limited, it was reasonable to extrapolate that it would help protect older people against COVID-19.

“The vaccine clearly offers some protection and since the older 65’s are your most vulnerable population, I’d think you want to get some vaccine into them sooner rather than later,” he said. “If Europe and the Germans want to be nitpicky, they can restrict its use, but I think giving older people this vaccine is better than nothing.”

The AstraZeneca shot would be the third COVID-19 vaccine given the greenlight by the EMA, after ones made by Pfizer and Moderna. Those were authorized for all adults and trials showed they provided more protection, with roughly 95% efficacy rates.

Two more vaccine makers also recently announced results, with Novavax saying this week that its shot appears 89% effective based on early findings and Johnson & Johnson saying its long-awaited single-shot vaccine was 66% effective at preventing moderate to severe illness. If those vaccines are eventually licensed, that could help alleviate the pressure on the world’s huge demand for the limited shots currently available.

The expected authorization of the AstraZeneca vaccine comes amid a bitter dispute between the drugmaker and the bloc after the company said it would sharply reduce initial deliveries from 80 million doses to 31 million.

Amid fears doses from AstraZeneca could be diverted outside the bloc, EU officials are expected to propose measures Friday that could be used to block vaccine shipments to non-EU countries.

In France, some elderly citizens getting a COVID-19 shot said younger people should be prioritized instead.

“Are we looking at this wrong way round?” asked Pierre-Antoine Lafortune, an 86-year-old who got a dose of a vaccine in Paris on Friday. “I’m getting vaccinated, but I think of our youths and how they can catch the virus, and it’s a pity that people in the prime of life can’t get immunity like us.”

The AstraZeneca vaccine has already been authorized in several countries, including Britain, India, Argentina and Mexico. The World Health Organization is also reviewing it; a recommendation from the U.N. health agency would allow its purchase and distribution to developing countries from a global program known as COVAX.