Story highlights "I will veto. I will unsign that so fast," Trump told a rally in Biloxi, Mississippi

Trump has regularly opposed stricter gun control laws following several mass shootings

(CNN) Donald Trump on Saturday vowed to "unsign" President Barack Obama's plans to tighten gun control via executive action, telling a packed rally in Biloxi, Mississippi, that he would protect the right to bear arms.

"There's an assault on the Second Amendment. You know Obama's going to do an executive order and really knock the hell out of it," Trump said. "You know, the system's supposed to be you get the Democrats, you get the Republicans, and you make deals. He can't do that. He can't do that. So he's going to sign another executive order having to do with the Second Amendment, having to do with guns. I will veto. I will unsign that so fast."

Obama will meet Monday with Attorney General Loretta Lynch to discuss options for tougher gun restrictions and is expected to announce in the coming days a new executive action with the goal of expanding background checks on gun sales. Described as "imminent" by people familiar with the White House plans, the set of executive actions would fulfill a promise by the President to take further unilateral steps the administration says could help curb gun deaths.

Earlier Saturday, CBS released a clip of Trump denouncing Obama's plan, arguing that "a tremendous mental health problem," not guns, is the cause of America's mass shootings.

"I don't like it," he told CBS's John Dickerson on "Face the Nation." "I don't like anything having to do with changing our Second Amendment. We have plenty of rules and regulations. It's plenty of things they can do right now that are already there. They don't do them."