(Bloomberg) -- President Joe Biden said Russia will “pay a heavy price” if any of its forces move across the border with Ukraine, seeking to clarify his comments from a news conference a day earlier.

Biden, in comments at the White House on Thursday, said he has issued clear warnings to Russia’s President Vladimir Putin, who has amassed 100,000 troops at the border with Ukraine.

“I’ve been absolutely clear with President Putin,” Biden said. “He has no misunderstanding: If any, any assembled Russian units move across the Ukrainian border, that is an invasion” that “will be met with severe and coordinated economic response that I’ve discussed in detail with our allies as well as laid out very clearly for President Putin. There is no doubt — let there be no doubt at all that if Putin makes this choice, Russia will pay a heavy price.”

In response to a reporter’s question on Wednesday, Biden said the U.S. and its allies had yet to agree on how to hold Moscow accountable over “a minor incursion.” The remark risked undermining weeks of escalating warnings from American diplomats and prompted White House aides to clarify -- before Biden had even finished speaking -- that any troop movement across the border would prompt “a swift, severe, and united response.”

The top U.S. and German diplomats also said Thursday that any Russian aggression against Ukraine would trigger a serious response, pushing to offset Biden’s remarks suggesting that Western allies might struggle to react to a small-scale attack. 

©2022 Bloomberg L.P.