(CNN) – In some of his harshest words yet, Newt Gingrich explained Friday why he didn't call rival Mitt Romney after the former Massachusetts pulled a decisive Florida primary victory earlier in the week.
Pointing to Romney's post-South Carolina campaign strategy, which turned noticeably negative against the former House speaker, Gingrich said Romney didn't earn any kudos.
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"They outspent me five to one to quote destroy Newt Gingrich?" Gingrich said in an interview on CNN's "The Situation Room with Wolf Blitzer." "You know, I think that doesn't deserve congratulations. I think that's reprehensible, I think it's dishonest, and I think it's shameful."
Gingrich took heat over not making the call after Romney's win on Tuesday, given that the former Massachusetts governor had congratulated Gingrich for his South Carolina win just 10 days prior.
Meanwhile, Romney's other rivals, Rick Santorum and Ron Paul, both picked up the phone on Tuesday.
"The other candidates all called, but I guess Speaker Gingrich doesn't have our phone number," Romney said Wednesday on NBC's "Today."
While campaigning ahead of Nevada's Saturday caucuses, Gingrich has largely maintained that Romney's full-throated attack strategy in Florida would come back to haunt him, arguing that voters prefer a positive campaign.
"Pretty hard to see how somebody is going to negatively carpet-bomb their way to the nomination," Gingrich said Friday on CNN. "Pretty hard to see how that nomination is going to be worth much if that's all they've got to show for themselves."
The candidate said he had no regrets over not making the traditional phone call.
"I feel very comfortable with exactly what happened after Florida," Gingrich said.
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