By Phil Stewart
CAIRO (Reuters) - U.S. Defense Secretary Robert Gates arrived in Cairo on Wednesday on an unannounced two-day visit where he is expected to discuss operations in Libya and offer U.S. assistance during Egypt's transition to democracy.
Gates will have his first face-to-face meeting with Field Marshall Mohamed Hussein Tantawi, the head of Egypt's ruling military council, since long-time ally U.S. Hosni Mubarak was toppled by a mass uprising.
Gates and Tantawi have spoken by phone more than a half-dozen times since the crisis erupted.
"(Gates) is especially appreciative of (Tantawi's) leadership and the performance of his military through a very tumultuous period in Egypt over the past several weeks," said Pentagon Press Secretary Geoff Morrell.
"And he is very encouraged -- especially coming out of this successful referendum -- that Egypt is trending in the right direction as it transforms itself into a democratic, civilian led government."
Gates will meet Prime Minister Essam Sharaf on Wednesday and Tantawi on Thursday.
A senior U.S. defense official said Gates would largely be in "listening mode" during the visit to Egypt, offering technical assistance ahead of parliamentary elections, which could happen as early as September.
Egypt was expected to be particularly interested in getting an update on the situation in Libya, where Western powers have attacked air and sea forces loyal to Muammar Gaddafi.
"The Egyptians obviously have great concerns not only because Libya's next door but because the number of Egyptians -- two million Egyptians in Libya," the official said, speaking on condition of anonymity.
(Reporting by Phil Stewart; Editing by Ralph Boulton)