WASHINGTON, May 18 (Reuters) - The United States believes the death sentence for former Egyptian President Mohamed Mursi is "unjust and undermines confidence in the rule of law," the State Department said on Monday.

State Department spokesman Jeff Rathke said Washington was also deeply concerned about "yet another mass death sentence" delivered by an Egyptian court.

The ruling against Mursi is not final until June 2. All capital sentences are referred to Egypt's top religious authority, the Grand Mufti, for a non-binding opinion, and are also subject to legal appeal.

(Reporting by Doina Chiacu; Editing by Eric Beech) ((doina.chiacu@thomsonreuters.com; 202-898-8322;))

Keywords: EGYPT COURT/MURSI USA