President Joe Biden and German Chancellor Olaf Scholz had an awkward exchange with a reporter Monday at the White House over the future of the Nord Stream 2 gas pipeline, according to CNBC.

The dialogue took place at a press conference during Scholz’s first visit to the White House.

Biden said Monday that Nord Stream 2 would be scrapped if Russia launches a military invasion of Ukraine, which Moscow’s troop movements strongly suggest is imminent. But Scholz refused to say the same.

“If Russia invades — that means tanks or troops crossing the border of Ukraine, again, then there will be no longer a Nord Stream 2,” Biden said at a joint press conference with Scholz. “We will bring an end to it.”

“But how will you do that exactly, since the project and control of the project is within Germany’s control?” asked Andrea Shalal of Reuters, who had posed the original question to Biden about Nord Stream.

“We will, I promise you, we’ll be able to do it,” Biden replied.

When the same question was put to Scholz, however, the German leader gave a very different answer.

“We have intensively prepared everything to be ready with the necessary sanctions if there is a military aggression against Ukraine,” he said, without mentioning Nord Stream. “It is part of the process that we do not spell out everything in public, because Russia should understand that there might be even more to come.”

“Will you commit today to turning off and pulling the plug on Nord Stream 2?” asked Shalal.

But Scholz would not. “As I already said, we are acting together. We are absolutely united and we will not be taking different steps,” he replied, ignoring Shalal’s question. The Nord Stream 2 natural gas pipeline between Russia and Germany was finished in September of last year, but it has yet to transport any actual gas.