On Wednesday, U.S. President Joe Biden said there was mounting evidence of anti-consumer behavior by oil and gas companies and asked the Federal Trade Commission to look into possible anti-competitive or "illegal conduct" in the market.

Biden had already asked the FTC in August to look into possible illegal conduct that was causing the spike in gas prices, but he said more action was needed because prices at the pump had continued to rise.

"I do not accept hard-working Americans paying more for gas because of anti-competitive or otherwise potentially illegal conduct," Biden said in a letter to FTC Chair Lina Khan on Wednesday. "I, therefore, ask that the Commission further examine what is happening with oil and gas markets and that you bring all of the Commission's tools to bear if you uncover any wrongdoing."

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