The nation's mayors are expected to ask Congress to push anew for stronger background checks for gun buyers.
City leaders will consider a resolution demanding gun control legislation during the 81st annual U.S. Conference of Mayors conference, which begins in Las Vegas on Friday.
The Democratic-controlled Senate voted against legislation in April that would have expanded background checks for firearm purchases to gun shows and online sales.
At the meeting, big-city leaders, including Los Angeles Mayor Antonio Villaraigosa, will also tell of their struggles with crime, foreclosures and unemployment rates, and share ideas for leadership strategies.
Mayors from Philadelphia, Baltimore, Atlanta, Phoenix and about 200 other cities are expected to attend.