Transportation Secretary James Burnley made it clear Wednesday that if the United States can't get provisions to protect U.S.-flag carriers, there won't be any deal with the Soviet Union on shipping.

A Soviet delegation has been here since Monday, meeting with U.S. officials, headed by Maritime Administrator John Gaughan. Marad is part of the Department of Transportation.It has been clear for months that the Soviets want a new maritime agreement that would open U.S. ports to them.

But U.S. carriers - who claim to have been burned by Soviet competitive practices under a prior agreement - are wary.

That earlier agreement was allowed by the United States to expire in 1981 in protest against Soviet policies toward Poland.

U.S. carriers don't want a repetition of rate-cutting by the Soviets, and they are especially opposed to Soviet ships operating freely in this country's trades with others - the so-called cross trades.

Mr. Burnley, during a press conference, declined to discuss the pending talks or to speculate on their outcome.

That wouldn't be kosher, he said.

He also declined to explain what sort of protection the United States may be insisting upon.

They (the Soviets) are interested in getting ports open, and we're interested in a fair shake for our carriers, he said.

The question is unchanged from the standoff that has existed since 1981 on any resumption of more normal shipping relations between the two countries.

If we don't get it, - protection for U.S. carriers - then there won't be any deal, he added.

The discussions were scheduled to run through today.

Soviet carriers are required to apply 14 days in advance for permission to enter U.S. ports, and they are barred from the cross trades. That restriction makes even service between the two countries awkward.

Under the previous agreement, ports in each country were opened for ships of the other, and provision was made for sharing the cargo moving between the United States and the Soviet Union.

No information has leaked directly from the discussions, but an informed industry source reported that no agreement will be reached this week.

The Reagan administration is committed to striving for better relations and understandings with the Soviet Union, especially on armaments. Expectations are that a new maritime agreement in that framework will be worked out soon.