President Obama is responding to a widespread outcry over gun violence with a new video, calling on the public to help him usher in new regulations in the wake of the mass shooting in Newtown, Conn.

“We hear you,” Obama says in the 2-minute, 49-second video posted on the White House’s YouTube channel. “You’ve started something, and now I’m asking you to keep at it. I’m asking for your help … to make sure the United States of America is a safer, stronger place for our children to learn and to grow.”

Administration aides said video is a direct response to several petitions on the White House’s Web site signed by a total of more than 400,000 that demand the president take action on gun control. One of the petitions has been signed by more than 196,000 people, making it the second-most popular petition in the 16 months the administration has been soliciting them under its “We the People” program.

In the video, Obama reiterates pledges he made earlier this week during a White House news conference, calling for a ban on military-style assault weapons and high-capacity ammunition clips, as well as stricter regulations to prevent criminals from accessing firearms. And he pledged again to push Congress in January to support new proposals that will be developed by a White House commission led by Vice President Biden.

The White House is releasing the video on the same day that the National Rifle Association has scheduled a news conference to offer its first extended public remarks after a heavily armed gunman shot and killed 27 people, including 20 children, before killing himself.

“It’s encouraging that many gun owners have stepped up this week to say there are steps we can take to prevent more tragedies like one in Newtown,” Obama says in the video.

White House aides said that preventing gun violence has quickly become one of the most popular issues in the history of the online petition program. Under that program, the Obama administration has promised to provide an official response to any petition that reaches 25,000 electronic signatures. So far, the White House has posted 82 responses on a variety of topics since launching the program, but Obama’s video is the first direct response from the president.

“We can’t do it alone. We need your help,” Obama says. “If we are to succeed it will take a sustained effort of mothers and fathers, daughters and sons … to speak up, call their members of Congress many times, stand up and say, ‘Enough’ on behalf of all our kids. That’s how change happens.”