US Vice President Joe Biden said President Barack Obama is "determined to take action" against gun violence.
He is weighing possible executive orders aimed at preventing further attacks like last month's shooting at a Connecticut school, Mr Biden said.
He was speaking to reporters at the start of a White House meeting with gun violence victims and gun-control advocates.
Mr Biden is leading efforts to craft a package of recommendations that Mr Obama has requested by the end of January.
The administration is considering a combination of executive actions and legislation and is determined to act quickly, Mr Biden said.
"We are not going to get caught up in the notion that unless we do everything we're going to do nothing," the vice president told reporters.
"There is a pretty wide consensus on three or four or five things in the gun safety area that could and should be done."
In a reversal, Wal-Mart Stores Inc said it would send a representative to Washington to meet Mr Biden tomorrow, after initially saying it would not send anyone.
Wal-Mart is the largest US gun seller.
After the Newtown shooting, in which 20 children and seven adults were killed by Adam Lanza, Mr Obama asked Mr Biden to come up with ideas to curb gun violence.
The president is expected to present many of them in his State of the Union address, traditionally delivered in late January.
Mr Obama has said he wants new gun control measures passed during the first year of his second term, but gun control is a divisive issue in the US, where the right to bear arms is enshrined in the constitution.
Mr Biden is due to meet the powerful US gun lobby, the National Rifle Association, tomorrow.
"We're reaching out to all parties on whatever side of this debate you fall," he said. "But the president is going to act. There are executive orders, executive action that can be taken."
No decision has been made yet on what those actions would be, he added.
Legislative measures are also under consideration, Mr Biden said.
Mr Biden's task force is examining legislation that would ban assault rifles, but is also looking at the role of violent movies and videogames in mass shootings and whether there is adequate access to mental health services.
New York governor proposes strict assault weapons ban
New York Governor Andrew Cuomo pledged to enact the strictest assault weapons ban in the US and outlaw all high-capacity magazines.
"Gun violence has been on a rampage as we know firsthand and we know painfully," Mr Cuomo said in his annual State of the State address, in which he committed New York to leading the country in enacting new gun control laws.
"We must stop the madness, my friends. And in one word it's just enough. It has been enough."
In Connecticut, Governor Dannel Malloy in his State of the State address urged US politicians to tighten federal gun control measures in response to the shooting at Sandy Hook Elementary School on 14 December.
"As long as weapons continue to travel up and down (interstate highway) I-95, what is available for sale in Florida or Virginia can have devastating consequences here in Connecticut," said Mr Malloy, who paused and fought back tears, his voice cracking, when discussing the tragedy at Sandy Hook.
New York and Connecticut already have among the toughest gun control laws in the country, but Mr Cuomo has complained New York's ban on assault weapons, for example, is so full of loopholes that it is unenforceable.
The law bans magazines with a capacity greater than 10 rounds but exempts magazines produced before 1994.
Mr Cuomo said it was virtually impossible to determine whether any magazine was made before or after that date, so he proposed eliminating large capacity magazines regardless of date of manufacture.
"Nobody needs 10 bullets to kill a deer. End the madness now," he said to a rousing ovation in the state capital Albany before state legislators, appointed officials, state employees and invited guests.
He also proposed requiring background checks for private sales of guns such as those taking place at gun shows; keeping guns from mentally ill people; and banning direct internet sales of ammunition in New York.