City Attorney Casey Gwinn, following a unanimous closed-session vote of the City Council Tuesday, sent a letter to the Anschutz Entertainment Group stating that the overtures could disrupt contract talks with the football team and hurt the bottom line of San Diego and its taxpayers.

Gwinn's letter states that interference could have "a material adverse impact" on San Diego.

The Chargers announced a week ago that Anschutz's group had contacted the team to gauge its interest in moving to a proposed new stadium in Downtown Los Angeles. The 1995 lease of Qualcomm Stadium between the city of San Diego and the Chargers allows the team to formally begin looking for a better deal after Dec. 1, 2002. The Chargers have long maintained they need a new stadium to remain competitive with other NFL franchises.

The lease, which was supposed to keep the Chargers in San Diego through 2020, has been a persistent thorn in the side of the city. In a widely publicized provision that outraged anti-tax advocates and other groups, the lease guarantees the Chargers the sale of 60,000 tickets per game. It also included a required $78 million expansion.

While not threatening a lawsuit, Gwinn's letter reads: "The city trusts that AEG will conduct its business affairs in Los Angeles without interfering with the contractual rights and obligations of the city and the Chargers under the agreement."