(Reuters) -Walgreens Boots Alliance ( WBA ) has suspended its quarterly cash dividend amid restructuring efforts, the U.S. pharmacy chain operator said on Thursday.

Shares of the company fell more than 7% in extended trading.

"The company's cash needs over the next several years, including with respect to litigation and debt refinancing, were important considerations as part of the decision to suspend the dividend," Walgreens said in a statement.

The decision comes weeks after the U.S. Department of Justice filed a lawsuit alleging that the pharmacy chain knowingly filled millions of prescriptions that lacked a legitimate medical purpose.

If found liable, Walgreens could face civil penalties of up to $80,850 for each unlawful prescription, according to the Justice Department.