The Supreme Court this week refused to hear Delta Air Lines' challenge to a rule barring it from offering non-stop flights between Salt Lake City and New York City's LaGuardia Airport.

The justices, without comment, let stand rulings that a so-called "perimeter rule" in effect for LaGuardia prohibiting non-stop flights to or from points more than 1,500 miles away is valid.LaGuardia is operated by the Port Authority of New York and New Jersey, which also runs Kennedy International Airport and Newark International Airport in the metropolitan New York area.

Until 1984, the Port Authority's perimeter rule for LaGuardia was informal and barred flights to or from points more than 2,000 miles away. The authority in 1984 imposed a formal 1,500-mile perimeter rule but allowed flights to and from Denver, which is 1,600 miles away, to continue.

Delta in 1986 sought to operate non-stop flights between LaGuardia and Salt Lake City International Airport. The Atlanta-based airline had operated such flights between Kennedy Airport and Salt Lake City for some years.

When the authority rejected the request, Delta sued. It charged that the local rule violated a federal law banning state or local agencies from enforcing any rule "relating to rates, routes or services of any air carrier."

A federal judge dismissed the suit, ruling that the perimeter rule is a valid exercise of the Port Authority's "proprietary powers."

The 2nd U.S. Circuit Court of Appeals upheld that ruling last year.

Justice Department lawyers urged the high court to reject the Delta appeal.

They said the 2nd Circuit court's decision is limited to those state or local agencies operating more than one airport.

"Since there is no indication that any other proprietor is likely to impose a perimeter rule, this decision is unlikely to have any significant impact upon the national air transportation system," the government lawyers said.