WASHINGTON (Reuters) - Sanctions targeting key Russian economic sectors would kick in swiftly if U.S. authorities determined the Kremlin had meddled again in a U.S. election, under a bill gaining momentum in the Senate on Wednesday.

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It was uncertain whether such a bill, or any other legislative response, could pass Congress after President Donald Trump at a Helsinki summit on Monday gave credence to Russian denials on the question of its interference in the 2016 U.S. election.

Lawmakers, alarmed with Trump’s conduct only days after U.S. authorities indicted 12 Russian spies on meddling charges, were trying to formulate a legislative response. Some have shied away from action, worried about how U.S. companies might be affected and how Trump might treat critics in an election year.

But Senator John Cornyn, the Senate’s second-ranking Republican, said Congress needed to do something, warning that Russia was sure to try to compromise November’s congressional elections.

“I have every confidence (Russia) will continue to try to up their game and create more chaos” this year, Cornyn told reporters in a Capitol hallway.

One measure gathering Senate support was an automatic sanctions proposal offered by Republican Senator Marco Rubio and Democratic Senator Chris Van Hollen.

It would require U.S. intelligence agencies to determine if any foreign government had interfered with a U.S. election soon after it occurred. If such a finding were reached, sanctions would take effect. In Russia’s case, they would target its energy, finance, defense, metals and mining sectors.

Cornyn and Senate Foreign Relations Committee Chairman Bob Corker were among Republicans who said the impact on U.S. corporations and European allies had to be weighed.

“What we don’t want to do is cut our nose off to spite our face,” Corker told Reuters in a hallway interview.

Rubio, speaking to reporters, brushed off such worries and predicted his bill would win easily if brought to a vote.

“My argument is, if you think sanctions are bad for American business, imagine a constitutional crisis. ... That would be terrible for America’s business,” Rubio said.

Republican Senator Jeff Flake and Democratic Senator Chris Coons were pushing on Wednesday for a Senate statement of support for U.S. intelligence agencies, whose work Trump largely disregarded in his Helsinki remarks.

Congress earlier this year provided $380 million for election security. Some lawmakers want to spend more than that and take other steps to beef up election cybersecurity.