The US-based company is sending 50 million single-shot vaccines to the European bloc over the next few months.
Pharma giant Johnson & Johnson began delivering its single-dose COVID-19 vaccine to the European Union on Monday.
Shipments were due to start at the beginning of the month, but were delayed due to production issues.
Dr. Peter Liese, an EU lawmaker from the same party as German Chancellor Angela Merkel, tweeted, "Johnson & Johnson began vaccine shipments to the EU today. Very good news. Vaccination target of #EU may now even be exceeded."
The US company committed to delivering at least 50 million doses by the end of June, and another 120 million doses between July and September, said EU industry commissioner Thierry Breton earlier this month.
A Johnson & Johnson spokesperson told dpa that the deliveries will go to all 27 EU states, as well as Norway and Iceland. The spokesperson did not say how many vaccines were included in the first delivery.
"This is the first step to fulfill the company's obligation to deliver 200 million doses to the European Union as well as Norway and Iceland in 2021," Johnson & Johnson spokesperson Silke Breitgoff told the dpa news agency.
Merkel warned that the current spike in infections in Germany was far too high, and said that the ongoing third wave of infections could be the toughest part of the pandemic.
"Testing will help us to build a bridge until vaccinations start to take effect," said Merkel at the opening of the Hannover Messe "digital edition" trade fair.
Germany's Robert Koch Institute for infectious diseases (RKI) recorded 13,245 new cases and 99 deaths on Sunday. That pushed Germany over 3 million confirmed cases in the outbreak.
General practitioners in Germany were allowed to perform immunizations in their offices beginning last week. That meant that nearly 2.5 million residents were able to get their first vaccine dose in the first week after the Easter holiday, nearly double any previous week.
Spain will initially take 300,000 Johnson & Johnson shots on Wednesday morning, said Health Minister Carolina Darias. The initial shots will primarily go to people aged between 70 and 79.
Spain hopes to meet its goal of vaccinating half of its adult population by July.
Belgium's coronavirus taskforce said it would receive close to 36,000 doses in the initial shipment, according to the Belga news agency.
The Johnson & Johnson vaccine was approved for use in the EU last month, the fourth vaccine to receive approval in the bloc after those made by BioNTech-Pfizer, Moderna and AstraZeneca.
kbd/rt (Reuters, dpa)