Washington (CNN) Sen. Rand Paul and Rep. Liz Cheney are engaged in a tense war of words over the US presence in Afghanistan, with Paul, a Kentucky Republican, accusing Cheney of wanting to engage in "endless wars" and the Wyoming Republican calling Paul a "big loser" for his failed 2016 presidential campaign.

On Wednesday, Paul tweeted a news article about Cheney's criticism of President Donald Trump's opposition to the war in Afghanistan, questioning why "some (neo-conservatives) continue to advocate for endless wars?" He added that we should "focus on America First, not Afghanistan."

In response, the Wyoming Republican said in a tweet that she "stand(s) with (Trump) and our men and women in uniform who will never surrender to terrorists, unlike @RandPaul, who seems to have forgotten that today is 9/11."

A day later, the two were still going head-to-head, with Paul casting Cheney and her father, former Vice President Dick Cheney, as "Never Trumpers" during an interview with CNN's Brianna Keilar on "CNN Right Now." Paul said the two "hate President Trump's foreign policy (and) they want to stay in Afghanistan forever," and cited the former vice president's tense conversation about Trump's foreign policy with Vice President Mike Pence earlier this year.

Hi @RandPaul I know the 2016 race was painful for you since you were such a big loser (then & now) with a dismal 4.5% in Iowa. No surprise since your motto seems to be "Terrorists First, America Second."



Here's a TBT courtesy of @realDonaldTrump. No truer words were ever spoken https://t.co/7MIM31ZuKl — Liz Cheney (@Liz_Cheney) September 12, 2019

The spat between the two prominent Republican lawmakers comes as Washington continues to reel over the sudden ousting of John Bolton, Trump's third national security adviser who often clashed with the President over foreign policy matters. Bolton, who also served under former President George W. Bush, was widely viewed as a hawkish member of Trump's Cabinet, and the feud between the two members of Congress is reflective of the contrasting opinions on foreign policy within the GOP.

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