The announcement came just days after the government said another homegrown vaccine, Soberana 2, had proved 62 per cent effective with just two of its three doses.

"Hit by the pandemic, our scientists at the Finlay Institute and Center for Genetic Engineering and Biotechnology have risen above all the obstacles and given us two very effective vaccines," President Miguel Diaz-Canel tweeted.

The announcement came from state-run biopharmaceutical corporation BioCubaFarma, which oversees Finlay, the maker of Soberana 2, and the Center for Genetic Engineering and Biotechnology, the producer of Abdala.

Both vaccines are expected to be granted emergency authority by local regulators shortly.

Cuba, whose biotech sector has exported vaccines for decades, has five coronavirus vaccine candidates.

The Caribbean's largest island is facing its worst COVID-19 outbreak since the start of the pandemic following the arrival of more contagious variants, setting records for daily coronavirus cases.

The Communist-led country has opted not to import foreign vaccines but to rely on its own.

Some experts said it was a risky bet but it appears to have paid off, putting Cuba in position to burnish its scientific reputation, generate much-needed hard currency through exports and strengthen the vaccination drive worldwide.

Several nations, from Argentina and Jamaica to Mexico, Vietnam and Venezuela, have expressed an interest in buying Cuba's vaccines, while Iran started producing Soberana 2 earlier this year as part of late-phase clinical trials.

Cuba's authorities have already started administering the experimental vaccines en masse as part of "intervention studies" they hope will slow the spread of the virus.

About a million of the country's 11.2 million residents have been fully vaccinated.

Daily cases have halved in the capital, Havana, since the start of the Abdala vaccination campaign a month ago according to official data.

Cuba has reported a total of 169,365 COVID-19 cases and 1170 deaths.

Australian Associated Press