After several delays, Ukraine on Tuesday finally received its first shipment of Covid-19 vaccines and said it would start inoculations from the following day.
The country of 40 million people is one of the poorest in Europe and one of the last in the region to begin a jab drive.
A plane carrying 500,000 doses of the AstraZeneca vaccine, produced at the Serum Institute in India -- the world's largest vaccine maker -- landed at Kiev's Boryspil airport, health ministry spokeswoman Sofia Fedchenko told AFP.
Ukrainian President Volodymyr Zelensky wrote on Twitter that his country "will start vaccination ASAP".
Health Minister Maksym Stepanov said on Facebook that the vaccines will undergo "urgent" routine cargo checks in the airport and then "immediately" be sent to the regions "so that we can start vaccinations".
In an afternoon press conference, Deputy Health Minister Viktor Lyashko said the jab campaign rollout would begin Wednesday.
"Tomorrow morning 11 cars will set off and deliver vaccines to regional warehouses," Lyashko told reporters.
Lyashko also reiterated a government policy that vaccination will be voluntary.
- Mobile vaccinations -
The health ministry on its website has set out a five-stage jab rollout. In the first stage, it plans to use mobile teams to innoculate around 367,000 people in priority groups.
They include healthcare workers treating Covid-19 patients and vulnerable risk groups, including people aged 60 and over, and those with chronic illnesses.
Zelensky had faced criticism for failing to obtain vaccines earlier in a country with a creaking healthcare system.
The president has blamed the delay on wealthier Western countries which reserved the Pfizer and Moderna vaccines in bulk and has urged the EU to help eastern European countries source them.
His government had originally announced that it would begin its vaccination campaign in mid-February, but the shipment of the first vaccine doses was delayed.
Ukraine is also awaiting delivery of eight million doses promised under the World Health Organisation's Covax programme.
On Tuesday, Deputy Health Minister Lyashko said Ukraine had greenlighted the use of the Pfizer vaccine and was now awaiting its delivery via the Covax programme.
Kiev has said it has also secured 17 million doses of vaccines developed by Novavax and AstraZeneca, including the 500,000 that arrived Tuesday.
It has also said it signed a contract to receive 1.9 million doses of the Chinese Sinovac vaccine.
Breakaway regions in the east controlled by Kremlin-backed separatists began a vaccine drive with Russia's Sputnik V jab in early February.
Ukraine earlier this month banned vaccines developed by "aggressor states", a designation Kiev has applied to Russia since 2015.
Ukraine's pro-Western leadership has repeatedly rejected calls from pro-Moscow politicians to approve Sputnik V, denouncing the vaccine as a geopolitical tool.
Ukraine has recorded over 1.3 million cases and more than 25,000 deaths from the virus.