The leading national mobile operator by customer numbers last year struck preliminary deals with Huawei and Nokia to build its 5G radio access network, which it plans to launch towards the end of 2020.

This is subject to certification of the vendors under rules that have not yet been finalised. As a back-up, Telefonica Deutschland has signed contracts with other suppliers who could step in if Huawei is excluded, CEO Markus Haas said.

"We have contracts with all the main vendors and would be in a position to make a switch within a few weeks," Haas told reporters on a conference call after Telefonica Deutschland reported a 5% drop in second quarter profits.

Telefonica Deutschland's wait-and-see approach contrasts with that taken by Deutsche Telekom, which has pressed ahead with building its 5G network largely on the basis of its existing agreements with Huawei.

Deutsche Telekom said this week its 5G network now reached 40 million people in Germany - nearly half the population.

Huawei faces an uncertain future in Europe after Britain decided to purge its equipment from 5G networks by 2027, siding with the United States in assessing it as a national security risk. Huawei denies it is such a risk.

German Chancellor Angela, under pressure from lawmakers to pursue a similar course, has put off a decision on Huawei until after the summer break.

Haas said Telefonica Deutschland would press ahead with its 5G strategy, which foresees covering Berlin, Hamburg, Munich, Cologne and Frankfurt this year. By the end of 2021, its 5G will be in 30 cities covering 16 million people.

He added that Telefonica Deutschland had chosen Ericsson of Sweden to deliver its 5G network core.

By Douglas Busvine