With the Biden administration and lawmakers becoming more and more concerned that Russia might be preparing to invade Ukraine, a seven-member delegation of U.S. senators traveled to Kyiv, where they met with Ukrainian President Volodymyr Zelensky and other top officials on Monday.

“Our bipartisan congressional delegation sends a clear message to the global community: The United States stands in unwavering support of our Ukrainian partners to defend their sovereignty and in the face of persistent Russian aggression,” Sen. Jeanne Shaheen (D-N.H.) said. Her sentiment was echoed by Sen. Rob Portman (R-Ohio), who said that Ukraine is defending its “territorial integrity against an increasingly aggressive Russia while also striving to enact critical domestic reforms to solidify its democracy,” making U.S. support “more important than ever.”

Shaheen and Portman were joined in Kyiv by Sen. Richard Blumenthal (D-Conn.), Sen. Kevin Cramer (R-N.D.), Sen. Amy Klobuchar (D-Minn.), Sen. Chris Murphy (D-Conn.), and Sen. Roger Wicker (R-Miss.). They met with Ukraine’s interior, foreign, and defense ministers, their teams, and energy executives, with Murphy telling reporters the senators stressed that the U.S. will keep providing “the defensive weapons systems that they need.”

Over the last year, Russia has been shifting its troops, and in the last several months an estimated 100,000 have made their way to the border near eastern Ukraine. The White House has warned that Russian operatives are now in eastern Ukraine, possibly preparing for a false-flag attack that would trigger an invasion by Russia. Moscow has said it has no intention of entering Ukraine, but wants the NATO alliance to stop expanding eastward. 

Last week, Senate Democrats introduced legislation that would impose sanctions on Russian President Vladimir Putin, several government and military officials, and banking institutions should an invasion take place.