Gun owners are bracing for an imminent policy proposal from the White House to tighten gun laws without Congressional approval, at the same time that Connecticut's governor has moved to use executive powers to stop people on federal terrorism lists from buying weapons.

Barack Obama's senior advisor, Valerie Jarrett, said that the president has asked members of his team to submit recommendations in a proposal he plans to review "in short order."

Speaking at a vigil for the victims of the Sandy Hook elementary school shooting in Connecticut on Wednesday evening, Jarrett said the proposals will include plans to expand background checks, among other measures. Gun control activists say they believe the White House will also move to close loopholes that allow people to buy firearms at gun shows and on the Internet without background checks.

On Thursday, Connecticut's Democratic Governor, Dannel Malloy, announced his intentions to sign an executive order that would prevent anyone on a federal terrorism watch list from purchasing guns in his state, which already has some of the strictest gun control measures in the country.

"Like all Americans, I have been horrified by the recent terrorist attacks in San Bernardino and Paris," Malloy told reporters. "This should be a wake-up call to all of us. This is a moment to seize in America, and today I'm here to say that we in Connecticut are seizing it."

The Sandy Hook massacre in December 2012 was the deadliest mass shooting at a school in US history. Yet even the deaths of 20 children and six faculty members who were gunned down in the attack were not enough to prompt meaningful gun reform. Since then, there are have been at least 161 school shootings in America, according to Everytown for Gun Safety, a group that tracks mass shootings.

After the mass shooting at Umpqua Community College in Roseburg, Oregon on October 1, White house officials said they were looking at ways to close a "gun show loophole" that allows purchases without background checks.

The recent massacres at a Colorado Springs Planned Parenthood and at a social services center for disabled people in San Bernardino, California have also revived continued calls for Congress to act on gun control.

"Congress should act to make sure no one on a no-fly list is able to buy a gun," Obama said in an address from the Oval Office after the San Bernardino shooting. "What could possibly be the argument for allowing a terrorist suspect to buy a semiautomatic weapon?"

Gun owners and advocates have counter-argued that the no-fly lists are not always accurate and barring gun ownership to the tens of thousands of people who feature on them would be a restriction of their Second Amendment rights.