France has issued a travel advisory to its citizens not to visit the Spanish region of Catalonia in a bid o curb further spread of COVID-19.

"Concerning the situation in Catatonia, which is displaying worsened indicators for infection, we strongly encourage French citizens to avoid going there until the health situation improves," French Prime Minister Jean Castex said on Friday.

According to Reuters, nearly 8,000 cases were diagnosed in Catalonia in the 14 days up to Thursday - almost half of the 16,410 detected throughout the country - despite guidelines for residents of regional capital Barcelona to stay at home.

France had said last weekend it had not ruled out closing the border between the two countries.

Between them, France and Spain have reported 486,833 COVID-19 infections and 58,614 deaths.

Castex said the government planned to reinforce controls at France's borders in the hope of better containing the pandemic.