(CNN) The Obama administration will announce a series of executive actions on Tuesday to combat gun violence in the U.S.

Among other things, the actions would expand mandatory background checks for some private sales. The administration would also provide more funding for mental health treatment, FBI staff and the Bureau of Alcohol, Tobacco Firearms and Explosives agents.

"These are not only recommendations that are well within my legal authority and the executive branch," Obama told reporters gathered Monday in the Oval Office. "But they are also ones that the overwhelming majority of the American people, including gun owners, support and believe in."

With Attorney General Loretta Lynch by his side, the President said he planned to roll out the new restrictions, aimed at combating a wave of recent shootings, in the coming days. He will hold a town hall on the topic Thursday that will air on CNN and is expected to make it a focus next week during his final State of the Union address.

Republicans in Congress and on the presidential campaign trail have blasted any attempt by the White House to crack down on gun rules.

"Pretty soon you won't be able to get guns," Donald Trump told CNN's Chris Cuomo Monday during an interview on "New Day." "It's another step in the way of not getting guns."

House Speaker Paul Ryan called out the President's "dismissiveness" toward the Second Amendment as well as Congress.

"While we don't yet know the details of the plan, the President is at minimum subverting the legislative branch, and potentially overturning its will," Ryan said in a statement Monday. "His proposals to restrict gun rights were debated by the United States Senate, and they were rejected. No President should be able to reverse legislative failure by executive fiat, not even incrementally."

Photos: Obama leads country through grief President Barack Obama condemned the slayings of three Louisiana law enforcement officers on Sunday, July 17, as he called on the nation to condemn violence against law enforcement. "We as a nation have to be loud and clear that nothing justifies violence against law enforcement," Obama said, speaking from the White House press briefing room. "Attacks on police are an attack on all of us and the rule of law that makes society possible." Hide Caption 1 of 16 Photos: Obama leads country through grief U.S. President Barack Obama speaks during an interfaith memorial service for the victims of the Dallas police shooting on Tuesday, July 12. Obama sought to unify the country during the somber memorial in Dallas for the five police officers slain in a sniper ambush during what had been a peaceful protest. The incident occurred amid a tragic week for the nation that saw Alton Sterling in Louisiana and Philando Castile in Minnesota killed during encounters with police. Hide Caption 2 of 16 Photos: Obama leads country through grief President Obama and Vice President Joe Biden place flowers at a memorial on Thursday, June 16, for the victims of the nightclub shooting in Orlando. At least 49 people were killed in the massacre, the deadliest mass shooting in U.S. history. Hide Caption 3 of 16 Photos: Obama leads country through grief Obama pauses on October 1 during a news conference about the mass shooting at Umpqua Community College in Oregon. Hide Caption 4 of 16 Photos: Obama leads country through grief Obama sings "Amazing Grace" during a service in June 2015 honoring the life of the Rev. Clementa Pinckney, a South Carolina lawmaker. Pinckney was one of nine people killed in a shooting at a church in Charleston, South Carolina. Hide Caption 5 of 16 Photos: Obama leads country through grief Obama and first lady Michelle Obama arrive for a memorial service in Fort Hood, Texas, in April 2014. Officials say Army Spc. Ivan Lopez took a .45-caliber handgun onto the military post, killing three people and injuring 16 before taking his own life. Hide Caption 6 of 16 Photos: Obama leads country through grief Obama pauses as he speaks in September 2013 about the shooting at the Washington Navy Yard, mourning what he called "yet another mass shooting" that took the life of American patriots. Hide Caption 7 of 16 Photos: Obama leads country through grief Obama tours a tornado-affected area in Moore, Oklahoma, in May 2013. A tornado that ripped through Moore hit 2,400 homes on a 17-mile path. Hide Caption 8 of 16 Photos: Obama leads country through grief Obama speaks at the Cathedral of the Holy Cross following the Boston Marathon bombings that killed three people and injured at least 264 in April 2013. Suspect Tamerlan Tsarnaev was killed during an encounter with police, and his brother, Dzhokhar Tsarnaev, was sentenced to death. Hide Caption 9 of 16 Photos: Obama leads country through grief Obama attends a memorial service at Baylor University in Waco, Texas, in April 2013. Fourteen people, nearly all first responders, died in an explosion at the West Fertilizer Co. Hide Caption 10 of 16 Photos: Obama leads country through grief In December 2012, 20-year-old Adam Lanza walked into Sandy Hook Elementary School in Newtown, Connecticut, and killed 20 children and six adults. At the memorial service, Obama said, "In the coming weeks, I will use whatever power this office holds to engage my fellow citizens -- from law enforcement to mental health professionals to parents and educators -- in an effort aimed at preventing more tragedies like this." Hide Caption 11 of 16 Photos: Obama leads country through grief Obama walks back to the Oval Office of the White House in July 2012. Obama cut short a campaign stop in Florida in the aftermath of the mass shooting at a movie theater in Aurora, Colorado. Twelve moviegoers were killed and 70 were injured by convicted shooter James E. Holmes. Hide Caption 12 of 16 Photos: Obama leads country through grief Obama speaks on the campus of Missouri Southern State University after a tornado ripped through Joplin, Missouri, in May 2011, killing 158 people. Hide Caption 13 of 16 Photos: Obama leads country through grief The President and first lady hold hands during a memorial service for the victims of a Tucson, Arizona, shooting. On January 8, 2011, Jared Lee Loughner shot six people and wounded 13 more, including then-Rep. Gabrielle Giffords. Hide Caption 14 of 16 Photos: Obama leads country through grief An explosion at the Upper Big Branch Mine in West Virginia killed 29 workers in April 2010. It was the worst U.S. mine disaster in 40 years. "All the hard work; all the hardship; all the time spent underground; it was all for their families. ... It was all in the hopes of something better," Obama said about the fallen workers. Hide Caption 15 of 16 Photos: Obama leads country through grief Thirteen people were shot and killed by Maj. Nidal Hasan at Fort Hood in November 2009. Speaking to an estimated 15,000 people at a memorial service, Obama called the act "incomprehensible" and vowed that justice would be done. Hide Caption 16 of 16

Over the weekend, Democratic presidential front-runner Hillary Clinton told Radio Iowa she applauded the President's new push, but warned any executive action was likely to fall short the comprehensive reform favored by most in her party.

"We've got to act," she said, "but I don't think that's enough and I think we're going to have to keep pushing forward on the political front and I intend to do that, to take on the gun lobby and to work with responsible gun owners."

On the trail Monday, Clinton again said she backed the President's efforts, but warned that voting a Republican into office in 2017 would effectively undo any progress that followed.

The most sweeping action currently being considered, an executive order defining who's "engaged in the business" of selling guns, would immediately require some private dealers to obtain a license and begin conducting background checks.

But efforts to even partially close the so-called "gun show loophole" are sure to prompt a rash of challenges in court. The resulting rulings and subsequent appeals are likely to drag on well beyond the end of this administration.

Obama's plan has already drawn heated criticism from Republicans, especially among the party's presidential candidates.

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In New Hampshire, Chris Christie again called the actions "an overreach."

"That's why I called him a petulant child yesterday," the New Jersey governor said on Monday. "That's what he's acting like."

Over the weekend, Marco Rubio said reversing Obama's potential actions , which he described as part a "war on the Constitution," would be his top priority upon entering the White House.

While on the trail Monday, the Florida senator recounted a recent news story of nine-year-old in Miami who died from a gunshot wound and who was on a sports team with his youngest son.

"No law in the world would have prevent that," Rubio told a crowd in New Hampshire, saying deaths from gun violence are a "societal issue."

"We as a society need to take responsibility for our children, for our families, for our communities and begin to address what is rotten what is broken in our culture that has led people to have no respect for human life," he added.

Ted Cruz, whose spokeswoman Catherine Frazier this weekend called Obama's plan "complete lunacy," said on Monday the President "is once again going to abuse his power to try seize our guns."

And in a phone interview with CNN, House Freedom Caucus Chairman Jim Jordan, R-Ohio, said he was still awaiting to hear the details on what the President will announce, but noted the GOP could mount a legal challenge to try to block implementation of any new rules.

"We may have to go to court just like we did with executive amnesty a year ago," Jordan told CNN.

Jordan also said Republicans could look to the appropriations process to block money, but said Republicans would discuss a more detailed response when they learn the full plan from the White House later this week.

However, a spending bill passed before the holidays funds government agencies through September 2016 means there's not much in the near term the GOP-led Congress could do to block funds to specific programs until the next fiscal year.