FRANKFURT (Reuters) – CureVac, the German biotech firm at the center of a row over alleged U.S. attempts to gain access to an experimental coronavirus vaccine it is developing, denied on Tuesday it had received U.S. offers for the company or its assets.

European Union leaders will on Tuesday discuss via videoconference how to prevent hostile U.S. takeovers of EU-based research firms at the forefront of developing drugs and vaccines against the coronavirus, officials said.

Media reports that Washington had tried to gain access to the vaccine stirred a political backlash in Germany, with economy minister Peter Altmaier and interior minister Horst Seehofer voicing support for keeping CureVac German.

The U.S. overture was first reported by Welt am Sonntag and confirmed to Reuters by German government sources. However, the U.S. ambassador to Germany, Richard Grenell, said on Twitter that the German newspaper report was wrong.

CureVac on Tuesday sought to play down any U.S. move.

“There was and is no offer from the U.S. neither with regard to taking over the company nor to have manufacturing slots reserved exclusively,” CureVac’s acting Chief Executive Franz-Werner Haas told journalists in a conference call, adding that its scientists had also not been lured to relocate.

The Tuebingen-based company, which is backed by the Bill & Melinda Gates Foundation, has said it hopes to have an experimental vaccine ready by June or July and to then seek the go-ahead from regulators for testing on humans.

If successful in clinical trials, the group would be ready to produce up to 10 million doses in one production cycle that typically lasts several weeks. More than one dose may be required to immunize a person.

Output could rise to a billion dosages in a single production cycle, said CureVac’s Chief Production Officer Florian von der Muelbe, at a new manufacturing site that the company is planning to build with financial support from the EU.

Others racing to deliver a vaccine include Johnson & Johnson’s <JNJ.N>, Moderna Inc <MRNA.O> and BioNTech <22UAy.F>.

CureVac did say earlier this month that its CEO at the time, Daniel Menichella, met U.S. President Donald Trump, Vice President Mike Pence, members of the White House Coronavirus Task Force and pharmaceutical companies to discuss a vaccine.

SAP <SAPG.DE> co-founder Dietmar Hopp, who owns a more than 80% stake in CureVac, was quoted as saying on Monday that he had also weighed in against a U.S. approach.

Hopp – who is also the owner of German first-division soccer team Hoffenheim – was asked about U.S. interest in exclusive rights to the CureVac vaccine under development by German sports broadcaster Sport1.

“He (Trump) spoke to the company and I was told about it immediately and was asked what I made of it and I knew immediately this was out of the question,” he was quoted as saying on Sport1’s website

Hopp and officials representing him were not immediately available to comment.

He had said in a statement on Sunday he was not selling and wanted CureVac to develop a vaccine to “help people not just regionally but in solidarity across the world.”

(Reporting by Ludwig Burger; Editing by Alexander Smith)