The World Health Organization (WHO) has taken note of the suspension in administration of the AstraZeneca vaccines by some countries, Director-General Tedros Adhanom Ghebreyesus said on Friday, adding that the agency is reviewing reports.

Italy, Thailand and Romania joined at least eight European countries this week in suspending the AstraZeneca shots either entirely or from specific batches, citing potential adverse effects including possible blood clots.

"WHO's Global Advisory Committee on Vaccine Safety systematically reviews safety signals, and is carefully assessing the current reports on the AstraZeneca vaccine," said Tedros. "As soon as WHO has gained a full understanding of these events, the findings and any changes to our current recommendations will be communicated immediately to the public."

He added that no deaths have been found to have been caused by COVID-19 vaccines so far.

Many countries worldwide continue to administer various vaccines in efforts to contain COVID-19, which by Friday had infected more than 118 million people globally and killed over 2.6 million.

WHO has so far approved four vaccines for emergency use and it noted that over 335 million doses of COVID-19 vaccines have been administered globally so far.

(With input from agencies)