Almost 300 sailors on £1bn destroyer HMS Diamond were the first in the task group to receive their jabs, sources have confirmed.
Hundreds more personnel are expected to be given their first inoculation in the coming weeks.
About 3,000 naval personnel – many of whom are based in Portsmouth – are expected to take part in the carrier strike group operation.
The task group, touted by the navy as ‘Europe’s most powerful’, will involve two Type 45 destroyers, two Type 23 frigates, support vessels from the Royal Fleet Auxiliary, an American guided-missile destroyer and a Dutch frigate.
Setting sail in May, the flotilla will visit the Mediterranean, Gulf and Indo-Pacific, with stops at various countries in each region planned.
It is anticipated sailors will receive their second jab, giving them increased protection from Covid-19, while at sea.
The announcement follows mounting pressure on the government – led by The News – to ensure military personnel were vaccinated before deploying overseas.
Armed forces minister James Heappey this week guaranteed troops would not miss out on their vaccine.
He said: ‘Service personnel will not be disadvantaged by their service in the UK or overseas. If they cannot safely be vaccinated in line with their age cohort whilst deployed, they will be vaccinated before leaving the UK.'
A retired Warrant Officer from Horndean, whose son is serving as part of the carrier strike group, previously raised his fears about those in the task force not being vaccinated before they deployed to Meon Valley MP, Flick Drummond.
Reacting to the latest news, the veteran said: 'At least the MoD have made the effort and I now feel a little more reassured that the deploying personnel will at least be covered by the first jab.’
However, Labour’s shadow armed forces minister Stephen Morgan accused the government of ‘dragging its heels’ for too long. The Portsmouth South MP said: ‘There needs to be clear, decisive action on which personnel will be prioritised in the vaccine rollout, particularly as the deployment for UK carrier strike group fast approaches.
‘It is welcome news HMS Diamond has received its first batch of the vaccine, but more needs to be done here.’
A government spokesman said the Foreign, Commonwealth and Development Office and MoD were ‘working jointly to ensure UK government and armed forces personnel overseas within the first nine priority groups are offered a vaccine’ in line with the UK population, including those in defence overseas bases and operational areas.”
The spokesman added: ‘We are committed to keeping our staff, their families and communities safe at home and overseas, and all our personnel are being vaccinated in line with national priority guidelines.’