The White House is weighing a far broader and more comprehensive approach to curbing the nation’s gun violence than simply reinstating an expired ban on assault weapons and high-capacity ammunition, according to multiple people involved in the administration’s discussions.

A working group led by Vice President Biden is seriously considering measures backed by key law enforcement leaders that would require universal background checks for firearm buyers, track the movement and sale of weapons through a national database, strengthen mental health checks, and stiffen penalties for carrying guns near schools or giving them to minors, the sources said.

To sell such changes, the White House is developing strategies to work around the National Rifle Association that one source said could include rallying support from Wal-Mart and other gun retailers for measures that would benefit their businesses. White House aides have also been in regular contact with advisers to New York Mayor Michael R. Bloomberg (I), an outspoken gun-control advocate who could emerge as a powerful surrogate for the Obama administration’s agenda…

In addition to potential legislative proposals, Biden’s group has expanded its focus to include measures that would not need congressional approval and could be quickly implemented by executive action, according to interest-group leaders who have discussed options with Biden and key Cabinet secretaries. Possibilities include changes to federal mental-health programs and modernization of gun-tracking efforts by the Bureau of Alcohol, Tobacco, Firearms and Explosives.