SEATTLE - Seattle city officials filed a lawsuit Monday to keep the SuperSonics from leaving town. The lawsuit filed in King County Superior Court was a countermove to the Sonics' attempt to be released from their lease on KeyArena.

Clay Bennett, right, Chairman of the Seattle SuperSonics basketball team announces at a press conference in Seattle, on Friday Sept. 21, 2007, that the team has filed a demand for arbitration over their lease of the Key Arena with the City of Seattle . Attorney Brad Keller, at left, of the firm Byrnes and Keller LLP is the team's attorney in this matter. (AP Photo/Marcus R. Donner)

According to the complaint, "The Sonics promised to 'play all home games ... exclusively'" at the arena at the Seattle Center through Sept. 30, 2010.

"The city, with the help of some fine lawyers, is standing up to a pro sports team," city attorney Tom Carr said at a news conference. "Too often, pro sports teams have run over local governments."

Sonics chairman Clay Bennett said Friday the club has requested an arbitration panel to rule that the NBA franchise does not have to play the final two seasons of its lease at KeyArena, arguing that the contract allows a negotiated buyout.

Such a ruling would allow the Sonics to relocate after this coming season unless the club secures a new arena in the Seattle area by Oct. 31.

Carr disputed claims by Bennett that the Sonics are losing money because of the arena lease, described by NBA commissioner David Stern as the worst for any team in the league.

"The issues with the Sonics' profitability at KeyArena have less to do with KeyArena than with the Sonics' ability to defend the high pick and roll," Carr said.

Former U.S. Sen. Slade Gorton, a lawyer who was instrumental in preventing the departure of the Seattle Seahawks under former owner Ken Behring, said at the news conference that while many disputes that could arise under the lease are subject to arbitration, the duration of the lease is clearly excluded.

The ultimate goal of the latest legal maneuver is to keep the Sonics in town permanently, whether under Bennett or a new, local owner, Gorton said

The lease makes it clear that the Sonics agreed to play all their home games in KeyArena for the duration of the agreement, and Bennett seems to have planned from the outset to move the club to Oklahoma City, Gorton said.

"They made the kind of demands that, from my perspective, were almost designed not to be met," Gorton said.