“In light of the most recent developments we must reassess the situation in particular regarding Nord Stream 2,” he told reporters in Berlin. “That will certainly take time, if I may say so.”
Mr Scholz said he had asked the economy ministry to take steps to make sure that certification could not take place at the moment.
“The appropriate departments of the economy ministry will make a new assessment of the security of our supply in light of what has changed in last few days.”
Western nations on Tuesday started imposing sanctions on Moscow following Mr Putin’s decision to recognise the independence of Donetsk and Luhansk and order troops across the border to “maintain peace”.
Nord Stream 2 is a 745-mile pipeline stretching between Ust-Luga near western Russia’s border with Estonia and Greifswald in northeastern Germany, intended for the delivery of natural gas to central Europe via the Baltic Sea.
The decision on Nord Stream 2 is a significant one for Berlin, which had long resisted pulling the plug on the project despite pressure from the United States and some European countries who argue it increases Europe’s reliance on Russia’s energy supplies. The pipeline would double the amount of gas flowing from Russia to Germany.
Construction on the project was completed in September 2021 at a cost of £8.3bn but it has yet to receive the necessary European regulatory approval to permit its operator, Russian state-owned gas giant Gazprom, to turn on the taps.