Germany would be forced to cut ties with China in the way it has with Russia should China attack Taiwan, the leader of Chancellor Olaf Scholz's Social Democrats (SPD) told the weekly Die Zeit in comments published on Wednesday.
Germany is working on a new China strategy that takes a more sober view of relations and aims to reduce dependence on Asia's economic superpower.
"We must realise that tomorrow, the day after tomorrow or in 10 years' time, the time may come when China crosses borders," Lars Klingbeil told Die Zeit.
"If China attacks Taiwan, our relationship with China will also fundamentally change, as is the case now with Russia."
Scholz has said relations with Russia cannot return to the times before Russia's attack on Ukraine.
Although Germany has helped to arm Ukraine to resist the invasion, a senior German lawmaker said on Wednesday that Germany would not provide Taiwan with weapons and had not been asked to do so.
China views democratically governed Taiwan as its own territory and has been ramping up military, political and economic pressure to assert those claims.
"The situation here is a different one. Our role is less military here. It's an economic question," said Marie-Agnes Strack-Zimmermann, the head of Germany's parliamentary defence committee, while on a trip to Taipei.
Klingbeil said Germany must become more independent of China, open up other markets and find other partners for trade in raw materials, adding: "That is the big lesson from our relationship with Russia."
Berlin's plans for a new China strategy mark a departure from its policies under former chancellor Angela Merkel, who took vast business delegations with her on her frequent trips to China and oversaw a boom in economic ties.
China became Germany's top trade partner in 2016.
In recent years, German politicians and business leaders have already advocated greater diversification in trade with Asia in response to President Xi Jinping's tightening grip over society and economy.
Shortly before leaving office in 2021, Merkel told Reuters she may have been naive at first in some areas of cooperation with China.
(Writing by Paul Carrel; Editing by Kevin Liffey)