WASHINGTON — More than two months after the Tucson shootings, the administration is calling together both the gun lobby and gun safety groups to find common ground. But President Obama has no plans to take the lead in proposing further gun control legislation, aides say, and the nation’s major gun rights group is snubbing the invitation.

On Tuesday, officials at the Justice Department will meet with gun control advocates in the first of what will be a series of meetings over the next two weeks with people on different sides of the issue, including law enforcement, retailers and manufacturers, to seek agreement on possible legislative or administrative actions.

The effort follows Mr. Obama’s call, in a column on Sunday in a Tucson newspaper, to put aside “stale policy debates” and begin “a new discussion” on ways to better enforce and strengthen existing laws to keep mentally unstable, violent and criminal people from getting guns.

But the National Rifle Association, for decades the most formidable force against proposals to limit gun sales or ownership, is refusing to join the discussion — possibly dooming it from the start, given the lobby’s clout with both parties in Congress. Administration officials had indicated they expected that the group would be represented at a meeting, perhaps on Friday.