New York (CNN Business) The West is already crushing Russia's economy. Now a bipartisan group of lawmakers want to limit Vladimir Putin's access to Russia's mountain of gold.

bipartisan bill introduced this week aims to ramp up the financial pressure another notch by making it harder for Moscow to use gold to prop up the crashing ruble. Existing sanctions have not directly targeted the Central Bank of Russia's roughly $130 billion in gold reserves.

"This would tighten the financial noose," Senator Angus King, an independent from Maine, told CNN in a phone interview.

The bill, introduced by King, Texas Republican Senator John Cornyn, Tennessee Republican Bill Hagerty and New Hampshire Democrat Maggie Hassan, would impose secondary sanctions on any American entities that knowingly transact with or transport gold from Russia's central bank holdings. It would similarly penalize American entities that sell gold physically or electronically in Russia.

"We are proposing to cut off one more avenue and increase the financial pressure to get them to stop this brutal campaign in Ukraine," said King, who praised the varying political backgrounds of the bill's sponsors. "You've never seen such a bipartisan bill."

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