(Bloomberg) -- A key U.S. lawmaker said Congress probably won’t ratify a global tax accord that world leaders aim to finalize by the end of October, potentially imperiling a deal aimed at reducing competition among governments with ever-lower corporate rates.

One half of the tax agreement is designed to help countries share the spoils from multinational firms like Facebook Inc. and Alphabet Inc.’s Google, and that part would require a treaty ratified by a two-thirds vote in the Senate, Republican Senator Patrick Toomey of Pennsylvania said Tuesday during a Senate Banking Committee hearing on Covid-19 relief.

Click here for Bloomberg’s TOPLive on Tuesday’s hearing

“I think that’s unlikely to happen,” Toomey said of achieving such a supermajority. Democrats and Republicans are currently evenly split in the 100-member chamber.

Group of 20 officials are aiming to finalize the agreement at a summit in late October. The Organization for Economic Cooperation and Development, which is overseeing the global talks among about 140 nations, says implementation would be possible as soon as 2023. 

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