By Patricia Zengerle and Arshad Mohammed

WASHINGTON (Reuters) - The United States said on Wednesday it would withhold deliveries of tanks, fighter aircraft, helicopters and missiles as well as cash assistance from Egypt's military-backed government pending progress on democracy and human rights.

The decision, described by senior U.S. officials and a congressional source, is a signal of U.S. unhappiness with the course that Egypt has taken since its army on July 3 ousted the country's first democratically elected president, Islamist Mohamed Mursi.

But the State Department issued a written statement making clear it would not cut off all aid and would continue military support for counterterrorism, counter-proliferation and security in the Sinai Peninsula, which borders U.S. ally Israel.

It said that it would also continue to provide funding that will benefit the Egyptian people in such areas as education, health and the development of the private sector.

"We will, however, continue to hold the delivery of certain large-scale military systems and cash assistance to the government pending credible progress toward an inclusive, democratically elected civilian government through free and fair elections," State Department spokeswoman Jen Psaki said.

The U.S. officials and the congressional source said the United States would withhold deliveries of M1A1 Abrams tank kits made by General Dynamics Corp, F-16 aircraft produced by Lockheed Martin Corp, and Apache helicopters and Harpoon missiles built by Boeing Co.

(Reporting by Patricia Zengerle and Arshad Mohammed; Writing by Arshad Mohammed; Editing by Sandra Maler and Peter Cooney)