Washington (CNN) Sen. Ted Cruz warned President-elect Donald Trump and other Republican leaders they may face a popular revolt if they don't carry through on some of their biggest campaign promises, including repealing Obamacare.

"If we're given the White House and both houses of Congress and we don't deliver, I think there will be pitchforks and torches in the streets," Cruz said Sunday on ABC's "This Week." "And I think quite rightly. I think people are so fed up with Washington, this election was a mandate with change and the most catastrophic thing Republicans could do is go back to business as usual."

Cruz was responding to a question about some Trump's flips on campaign promises, just weeks after winning the election, including saying he would not pursue a prosecution of Hillary Clinton and that he would like to keep pieces of Obamacare.

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Republican leaders in Congress have promised to help Trump push through top priorities, but Senate Majority Leader Mitch McConnell has cautioned against Republicans going too far, lest they face a backlash at the ballot box. Democrats, who similarly swept into power in 2008, were sharply rebuked by voters in 2010.

Cruz, who was an ardent opponent of Trump until the final months of the campaign, was asked about his charges that Trump was a "pathological liar" and "utterly amoral."

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