WASHINGTON — Washington is keeping an eye on what comes out of Iranian Parliamentary Speaker Hashemi Rafsanjani's visit to Moscow. US officials are not alarmed. They see the visit as part of Mr. Rafsanjani's effort to play off the East and West, rather than a permanent tilt to the Soviets. The Bush administration is hopeful about Soviet assurances that they ``will not lean too far forward'' during the visit, nor agree to sell Iran ``any new military systems.'' The assurances were given during US-Soviet consultations last week. US officials say the restraint bodes well for US-Soviet regional cooperation .