WELLINGTON, June 21 (Reuters) - New Zealand's medicines regulator Medsafe has provisionally approved the use of the Pfizer/BioNTech coronavirus vaccine for 12- to 15-year-olds, Prime Minister Jacinda Ardern announced on Monday (Jun 21).

“After careful consideration of the most up-to-date scientific and medical data available, Medsafe has announced provisional approval for our young people to be given the Pfizer vaccine,” Ardern said in a statement.

There are around 265,000 children in the 12 to 15 age bracket in New Zealand, she said.

About 1 million doses of the Pfizer vaccine have so far been administered in New Zealand, a nation of 5 million people.

The country's medical authorities are yet to approve the use of any other vaccine, including AstraZeneca.

Pressure has been mounting on the government to speed up vaccinations and reopen its borders. Ardern has said having more people vaccinated gives the nation more options at the border.