By Sergio Goncalves

LISBON (Reuters) - Portugal's centre-right government will keep the previous administration's ban on telecoms firms using Chinese equipment in their 5G networks, a minister said, despite the projected cost of a position that is among the toughest in Europe.

In May 2023, under the previous Socialist government, Portugal's CSSC cybersecurity board banned Chinese equipment from high-speed 5G mobile networks as well as from 4G platforms used as the basis for the new technology.

The CSSC is the prime minister's consultative body and its move was a blow to efforts by Chinese technology giant Huawei to enter Portugal's 5G market and possibly extend existing contracts.

The new government took over in April.

"There are certain policies that must have continuity and security is one of them," Infrastructure Minister Miguel Pinto Luz told broadcaster NOW late on Monday.

Europe and the United States are concerned that Chinese involvement in critical infrastructure could compromise security, a view rejected by Beijing and Huawei. In September, Huawei filed a lawsuit with a Lisbon court against the CSSC's move.

Pinto Luz said the working group that backed the CSSC's position highlighted the need to make the telecoms system "less permeable" to potential threats.

He acknowledged Portugal was taking a stricter line than some European countries and more in line with the United States, but said the "world has changed ... and there is an ever-growing economic and geopolitical war between the two poles".

Portugal's main telecoms operators, Altice, NOS, and Vodafone, have already said they would not use Huawei's technology in 5G core networks, but they would still have to dispose of the equipment in all of their infrastructure.

A study by consultants EY for Huawei, released on Monday, estimated the exclusion of the Chinese technology could cost the economy more than 1 billion euros ($1.1 billion), including 339 million euros in replacement costs.

The minister played this down, however, saying operators would have "a wide time window" to replace equipment.

($1 = 0.9062 euros)

(Reporting by Sergio Goncalves; Editing by Mark Potter)