Distribution of the second Covid-19 vaccine in Wales begins on Monday.
The Oxford University/AstraZeneca vaccine was approved for use in the UK last week by the UK's medicines regulatory body - the Medicines and Healthcare Products Regulatory Agency (MHRA).
Wales will receive its allocation of vaccine based on population but it is expected that at least 40,000 doses will be made available here within the next two weeks.
Unlike the Pfizer BioNTech version, this latest vaccine does not need to be stored at ultra-cold temperatures.
Two doses of the vaccine will be needed between four and 12 weeks of each other, following a change in advice from the Joint Committee on Vaccination and Immunisation (JCVI) that previously only recommended a four-week gap.
The change in advice is based on the recommendation that as many people as possible in the top priority groups should be offered a first vaccine dose as a priority.
Health Minister Vaughan Gething said: "Today marks a key milestone in our fight against the Covid-19 pandemic.
"The roll-out of the AstraZeneca vaccine has been called a ‘game changer’ and this is true - its potential should not be underestimated.
"In less than a month Wales’ NHS has mobilised the largest vaccination programme our country has ever seen and so far more than 35,000 people have received their first dose.
"Now, only five days since regulatory approval of the new vaccine for use in the UK, a second vaccine is here and ready for use, significantly adding to Wales’ defences in the face of coronavirus and protecting our most vulnerable."
Latest figures, to the end of December 27, show that over 35,000 people have received the first dose of the Pfizer/Bio BioNTech vaccine within three weeks of the start of the vaccination programme.
The Welsh government said every health board in Wales would receive its vaccine allocation in proportion to the size of its priority population and ability to deliver it.
Senior Responsible Officer for Wales’ Covid-19 Vaccine Programme Dr Gillian Richardson said: "It is fantastic news that there is now a second vaccine to help protect our communities’ most vulnerable from the harms of Covid-19.
"Pace will be governed by supply, which will start slowly this week but build vastly over the coming weeks and months.
"However, vaccinations are happening in GP surgeries from today and we will also see an increase in our vaccination centres over the course of this month.
"It is so important that people continue to wait their turn for the vaccine – you will be contacted when your time comes.
"Please do not contact your GP or local pharmacy and add unnecessary pressures to their workload."