U.S. Agrees to Have Role in Spaceport : Technology: The private Australian satellite-launching venture hopes to garner a fifth of the worldwide business.

The White House on Wednesday conditionally approved U.S. participation in Australian plans for the world’s first private spaceport, a project that relies on a mix of U.S. technology and Soviet rockets.

Bruce Middleton of the Australian Space Office in Canberra said the authorization clears the way for Connecticut-based United Technologies Corp. to provide needed technical expertise.

Cape York Space Agency, a Brisbane, Australia-based company, plans to build the $623-million spaceport and hopes to use Soviet rockets to put satellites in orbit by 1995. The agency expects to capture 20% of the world satellite launch market by 2000.

United Technologies had to seek U.S. government approval under laws restricting high-technology deals involving the Soviet Union.

The U.S. approval is conditional on the Soviet Union limiting launch activities to the Cape York base in Australia’s northern state of Queensland or another site outside the Soviet Union, the statement said.

The venture must also adhere to U.S. laws restricting technology transfers to Communist states, it said.

The Cape York Space Agency has an exclusive agreement with the Soviet Glavkosmos group to use advanced Zenit rockets to launch satellites from a marshland site on the northeast coast of Queensland.