Senators introduced legislation Tuesday that will request the Treasury Department begin offering money to individuals and organizations in exchange for tips leading to hidden Russian assets that can be seized by U.S. authorities. It remains unclear how much these rewards would be, or how the Treasury would pay them out. 

The bill also calls for a strengthening of Biden’s sanctions policy, allowing officials to seize Russian-owned assets and auction them off. The proceeds from these auctions will then be used to pay for humanitarian relief efforts in Ukraine.  

The bill, known as the Asset Seizure for Ukraine Reconstruction Act, is sponsored by Sens. Sheldon Whitehouse (D-R.I.), Lindsey Graham (R-S.C.), Richard Blumenthal (D-Conn.), and Roger Wicker (R-Miss.).

“Putin and his oligarchs stow their dirty money in rule-of-law nations by purchasing mansions, mega-yachts, artwork, and other high-value assets. We ought to seize those ill-gotten luxuries and put them to use helping the Ukrainian people,” Sen. Whitehouse said in a statement on Tuesday, reported by the Washington Post.

Sen. Whitehouse’s office did not immediately respond to Fortune’s request for comment.

The Biden administration’s current sanctions regime against Russia already makes sanctioned Russian-owned assets in the U.S. “frozen and inaccessible.” The senators’ proposed bill would also give the president power to confiscate and liquidate those assets.

If passed, the legislation will allow U.S. officials to seize and auction off yachts, homes, artwork, and other assets owned by sanctioned Russian citizens that are worth more than $2 million.  

The bill states that all proceeds from auctioning off seized Russian assets should be directed towards supporting Ukraine, creating funds to deliver weapons and other tactical advantages to the Ukrainian military, funding humanitarian work, and reconstruction efforts once the conflict is over. The bill’s provisions would also see some funds used to help resettle Ukrainian refugees in neighboring European countries and in the U.S.

The Biden administration has been reluctant to amend his sanctions regime, and the White House and Congress have disagreed on how sanctions should be implemented. It’s unclear if the president will support the provisions in this particular bill.

This isn’t the first time a bipartisan group in Congress has pushed Biden to be more assertive with his sanctions. The administration has received mounting pressure from Congress to send planes and weapons to aid in the Ukrainian resistance efforts. And at the beginning of March, bipartisan lawmakers pleaded with the White House to ban Russian oil imports, an effort that was ultimately successful. 

Western countries have seized plenty of Russian assets since sanctions were put in place, including yachts, private jets, and houses, but with the current sanctions regime, officials are not able to do much with these assets after seizing them. Even if a frozen asset is inaccessible to its sanctioned owner, they are still technically owned by them, meaning that many of these Russian yachts are simply rusting away while anchored to their docks. 

But even if Biden is reticent to start seizing and selling off Russian-owned assets from sanctioned individuals, his hand may soon be forced by his Russian counterpart, President Vladimir Putin, who is exploring solutions to legally seize the assets of Western companies still in Russia. 

Putin recently made some headway on these efforts by initiating the seizure of over 500 foreign-owned planes that were leased to Russian airlines before the sanctions came into effect, worth a total of around $10 billion.