Seven states join effort to stop AT&T/T-Mobile deal

WASHINGTON (Reuters) - Seven states have joined the U.S. Justice Department's lawsuit to stop AT&T's <T.N> proposed purchase of T-Mobile USA, the Justice Department said on Friday.

Attorneys general from California, Illinois, Massachusetts, New York, Ohio, Pennsylvania and Washington have signed onto the effort to stop the deal that would merge two of the four large national cellphone carriers.

"We have had an excellent working relationship with a number of state attorneys general and they have provided invaluable assistance throughout our investigation," the Justice Department said. "We are pleased that these states have joined the department in its lawsuit."

The Justice Department says the acquisition of T-Mobile USA by AT&T would lead to higher wireless prices.

(Reporting by Diane Bartz in Washington)