In an interview on "Hannity" Monday, Republican U.S. Sen. Lindsey Graham revealed under what circumstances he would support a no-fly zone in Ukraine, and urged the Biden administration to take clear and decisive action against China.

Graham said that he did not currently support a no-fly-zone, which NATO-member Estonia became the first interorganizational ally to support.

"But if there's the use of chemical weapons by Putin against the Ukrainian people, I would support a no-fly zone because that would be breaking every war crime rule in the book," Graham added.

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"And the ban on chemical weapons would be nothing if we didn't act with a no-fly zone. But right now, no boots on the ground, no-fly zone.

Sen. Lindsey Graham, R-S.C. 

Sen. Lindsey Graham, R-S.C.  (Fox News)

Graham went on to say that China is "trying to bail out Putin." 

"If Putin loses, China loses," Graham added, encouraging the Biden administration to not "make the same mistake with China you did with Russia." 

"If you believe the Chinese are going to help Putin survive by providing military equipment and economic assistance … put on the table for China to read, the sanctions that will come [their] way, if [they] help Putin," he said.

Vladimir Putin and Xi Jinping

President Vladimir Putin and Chinese President Xi Jinping pose during a meeting at the Diaoyutai State Guesthouse on Feb. 4, 2022. (Photo by Alexei DruzhininTASS via Getty Images)

"I will help you as a Republican, Mr President, President Biden, if you will write down sanctions, secondary sanctions against China, what will happen to the Chinese economy if they bail out this war criminal, Putin. I will be your best ally in the U.S. Senate"

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Graham encouraged Biden to write down potential sanctions against China, "because nobody believes you unless you write it down."