Taiwan has begun administering its first domestically developed Covid-19 vaccine, amid criticism that its approval was rushed.

The island's health ministry authorised emergency use of the Medigen vaccine last month although clinical trials are yet to be completed.

Taiwan's vaccination efforts have been hampered by delivery delays and hesitancy amongst its population.

President Tsai Ing-wen led the way in receiving the Medigen jab on Monday.

At the time of its approval, the vaccine - made by Medigen Vaccine Biologics Corp - has yet to complete phase three trials but was granted emergency approval by regulators.

The company said there were no major safety concerns and studies showed that antibodies created were "no worse than" those created by AstraZeneca's vaccine.

It's expected to complete the final round of trials being held in Paraguay later this year.

Medigen, whose Chinese name literally means "high-end", is a recombinant protein vaccine, similar to the vaccine developed by Novavax.

The Novavax jab uses a more traditional method of recreating part of the spike protein of the virus to stimulate the immune system.

"We have done so many experiments, everyone has seen how safe our vaccine is. There are so few side effects, almost no fever and so on. So I think everyone can rest assured," Medigen's Chief Executive Officer Charles Chen told Reuters.

However, its rollout has been clouded by accusations, many from the main opposition party, the Kuomintang (KMT) that the vaccine is unsafe or that its entry into the market was rushed.

Two prominent members of the party approached a court to revoke the emergency use approval due to insufficient testing.

One of them said there is no need for Taiwanese people to be treated as "white rats in a laboratory".

Taiwan has been using Moderna and AstraZeneca vaccines, but President Tsai held off receiving her shot until the Medigen jab was ready.

The process of her receiving the jab was streamed live on her Facebook page - when she was asked if she was nervous, she replied, "no".

More than 700,000 people have already signed up for the Medigen vaccine, which requires two doses 28 days apart.

Taiwan is currently reporting around 10 cases a day, and was considered to be one of the most successful places at containing Covid.

But an outbreak in May raised concerns about the arrival of the highly contagious Delta variant.

Five million doses have been ordered, but the government has said nobody will be forced to get the vaccine.

Less than 5% of Taiwan's 23.5 million population is fully vaccinated with around 40% having received just one dose.