Turkey’s flag carrier, Turkish Airlines, will restart flights from the United Kingdom and Denmark, the company’s CEO Bilal Ekşi said Wednesday.

Turkey had temporarily suspended flights from the two countries back in December due to fears over new strains of the coronavirus.

Ekşi said on Twitter passengers will need to have a negative PCR test within 72 hours of the flight, citing a decision by authorities.

Flights from Brazil and South Africa remain grounded over highly contagious and potentially deadlier strains reported in both countries.

The three major strains – British, South African and Brazilian – have caused dozens of countries to suspend flights after scientists said the new variants were believed to be spreading up to 70% faster than others.

The World Health Organization reported in January that mutated COVID-19 variants had spread to 70 countries.