WASHINGTON (MarketWatch) — President Barack Obama on Wednesday announced a sweeping effort to tighten U.S. gun-control laws.

Surrounded by children and families of victims of the Newtown, Conn., elementary-school shooting, Obama urged Congress to act swiftly on his proposals.

Obama said that 900 people have been killed by gunfire in the month since the Newtown shooting in December, in which 20 elementary-school children and six adults were shot to death by a young man who then committed suicide. Police said the shooter killed his mother before going on the rampage. Read related blog on assault weapons and murders.

Obama on guns: 'With rights come responsibilities'

“Every day we wait, that number will keep growing,” the president remarked, calling the situation “an epidemic of violence.”

Analysts say the White House will have a hard time getting its proposals through the Republican-controlled House of Representatives.

Obama also must persuade senior Democratic leaders in Congress to push the gun-control measures.

A spokesman for House Speaker John Boehner indicated the House would wait for the Senate to pass a bill.

Obama called for a grass-roots effort to persuade Congress to support his plan. “If Americans of every background stand up and say enough … then change will come,” he said.

Gun stocks rose as the president launched his push. Shares of Smith & Wesson Holding Corp. US:SWHC ended nearly 6% higher, and Sturm, Ruger & Co. RGR, -1.14% shares gained 5%.

Obama proposed a ban on large ammunition magazines and a requirement for universal background checks for gun buyers. Gun-control advocates said that 40% of gun sales occur without background checks.

“That is not safe; that is not smart,” according to the president, who continues to back a ban on assault weapons. Observers said he would not make it a high priority because of congressional opposition.

The president speaks on proposals to reduce gun violence with VP Joe Biden. Reuters

Rep. Carolyn McCarthy, a Democrat from New York elected to Congress by promising to fight for gun control, said that an outright ban on assault weapons would not pass Congress. But a package of reforms could pass the Senate, she added.

In the days leading up to the president’s announcement, gun-control advocates have said that the assault-weapons ban was a low priority and that they would instead push for universal background checks, which has a better chance of passage.

Obama also signed almost two dozen executive orders setting out immediate actions the federal government can take to reduce gun violence, including ordering federal agencies to do research on gun use and bolstering mental-health training.

Opposition from the National Rifle Association is expected to be intense. The gun lobby recently posted a video on the Internet saying that Obama’s children are protected by the Secret Service.

In a statement Wednesday, the NRA said that it would continue to focus on legislative efforts to securing schools, fix “our broken mental-health system” and prosecuting violent criminals.

“Attacking firearms and ignoring children is not a solution to the crisis we face as a nation,” the gun lobby added.

The president’s framework is based on recommendations prepared by a task force headed by Vice President Joe Biden.