"We will do everything we can to prevent it [dependence on one supplier]. It is always possible to switch to LNG, many European countries have big terminals," Altmaier said at a press conference.
"Those who supply us with gas through pipelines should also know that as a result of an unfair increase in prices, ... sources of supply may change," the minister warned.
Germany's gas storage facilities are currently 75% full, which exceeds the level seen in 2015 when this volume was sufficient for the whole winter, Altmaier added.
The European Union has seen a spike in natural gas prices over the past few months, driven by growing energy demand amid an economic recovery from months of lockdowns, and a limited supply. Peak price of gas futures in Europe exceeded $1,900 per 1,000 cubic meters in early October.