In a statement, the embassy justified the decision with the "serious and complex" situation of the Covid-19 pandemic in Portugal and the need to avoid "cross-infection in transit.

The embassy will no longer accept applications for the issue of a green health code from permanent residents in Portugal wishing to travel to China via another country.

There is currently only one direct link between China and Portugal, with Chinese airline Beijing Capital Airlines flying between Lisbon and Xi'an, in Shaanxi province, every Thursday and Saturday.

The Chinese embassy in Portugal also stopped issuing health codes for passengers living in other countries that have direct links with China, but who wanted to fly from Lisbon, the statement said.

The only exception is passengers coming from countries without direct flights to China who have a green health code issued by the Chinese Embassy in their country of origin.

At the beginning of January the embassy had already required passengers changing flights in Portugal to present two negative tests for the new coronavirus, carried out at different locations, before being authorised to board the flight to China.

On 17 January, central China's Shaanxi province recorded an imported case of Covid-19, a 42-year-old Chinese woman who had flown from Lisbon to Xi'an on 3 January.

In October, within three days, Shaanxi recorded three cases of Covid-19, all Chinese nationals returned to the country via Lisbon. One of the men came from Angola, another from Cape Verde and the other from Bolivia and also passed through Sao Paulo, Brazil.