BERLIN, Sept. 9 (Xinhua) -- The European Commission is planning to order 200 million doses of a potential COVID-19 vaccine from the German pharmaceutical company BioNTech SE and U.S. company Pfizer, the companies said Wednesday in a statement.

The proposed agreement also includes an option to purchase an additional 100 million doses of the investigational BNT162 vaccine candidate for member states of the European Union (EU), according to the statement.

"We are pleased to have concluded exploratory discussions with the European Commission, which would be our largest initial order to date," said Ugur Sahin, chief executive officer (CEO) and co-founder of BioNTech.

The vaccines for the EU would be produced at BioNTech's facilities in Germany as well as Pfizer's production site in Belgium, according to the companies. Deliveries of the potential COVID-19 vaccine are planned to start by the end of 2020.

"We have activated our supply chain, most importantly our site in Belgium, and are starting to manufacture so that our vaccine would be available as soon as possible, if our clinical trials prove successful and regulatory approval is granted," said Albert Bourla, chairman and CEO of Pfizer.

The delivery schedules are subject to the ongoing clinical trials. A global study on the potential vaccine with up to 30,000 participants already started in late July. "The Phase 2/3 trial enrolment to date has exceeded 25,000 participants with a second dose underway," the companies noted.

BioNTech and Pfizer are aiming to file for regulatory approval for BNT162b2 in October if the current clinical study on the potential COVID-19 vaccine proved successful.

Ursula von der Leyen, president of the European Commission, said that she was happy to announce that "we have concluded talks with BioNTech-Pfizer for an initial purchase of 200 million doses of future coronavirus vaccines."

"This is the sixth pharma company with which we have concluded talks or signed an agreement for potential vaccines, in record time," added von der Leyen in a statement on Wednesday.