Finland has postponed the use of Johnson & Johnson's Covid-19 jab in its national vaccination programme.
The country already ordered millions of doses of the vaccine, which was approved by EU regulators in March.
But, like the AstraZeneca jab, J&J is an adenoviral vector vaccine linked to rare blood clot risks in a relatively small number of recipients.
J&J has seen widespread use in the United States and other countries, but at the end of April there were reports of blood clots in eight recipients of the vaccine in the US. By that time it had been administered to more than seven million people.
Not long after reports emerged about AstraZeneca's blood clot incidents, Finnish health authorities decided to only give it to people over the age of 65.
Hanna Nohynek, chief physician at the Institute for Health and Welfare (THL) said there was no immediate need to start using J&J's jab.
"In the current epidemic situation in Finland, there is no need for the Johnson & Johnson vaccine, as it would be given to people over the age of 65, like the AstraZeneca vaccine. The majority of those people in that age group have already been vaccinated," Nohynek said in a statement.
However, she said the matter will be re-examined if the epidemic situation worsens.
In total, Finland has committed to purchase 2.4 million doses of the J&J vaccine, which unlike mRNA jabs only needs a single dose to be fully effective and also lasts a long time.
THL announced on Wednesday that, going forward all residents in Finland would only receive mRNA vaccines, which in practice means jabs from Pfizer-Biontech or Moderna.
The health institute also said that people over 65 who have already gotten one AstraZeneca dose now had the option to receive an mRNA vaccine for their second.
"Our recommendation remains that people over the age of 65 should get the same Covid vaccine that they received earlier. However if people who got the AstraZeneca vaccine [for the first jab] refuse to take another, they can get an mRNA vaccine if they wish," Emma Kajander, a THL specialist physician, said in the statement.
The period between mRNA vaccine doses in Finland remains 12 weeks, but medical reasons like being treated for cancer can prompt a shortening of the interval, according to THL.