The United States and the Soviet Union concluded their first major consultations on the Middle East in more than seven years here today but gave no indication whether the talks could lead to new peace negotiations to break the impasse in the Arab-Israeli conflict.

The two delegations, composed of senior diplomatic specialists in Middle East affairs, held five hours of discussions at the U.S. Embassy today after meeting at the Soviet Embassy for five hours on Tuesday.

The Soviet team, led by Vladimir Polyakov, head of the Near East Division of the Foreign Ministry, departed in two cars without speaking to reporters.

U.S. officials said that statements would be released "at some time" in Moscow and Washington describing the nature and contents of the talks.

In Washington, a State Department spokesman said there would be no statement until the American delegation head, Assistant Secretary Richard W. Murphy, has returned to the United States.

A Soviet statement released in Moscow simply reported the conclusion of the talks and said: "Main attention was devoted to the problem of achieving an all-embracing and just settlement of the Middle East conflict," Washington Post correspondent Dusko Doder reported.

The discussions were considered significant because they extended Soviet-U.S. dialogue beyond arms control to an area of vital regional interest. The last time the two countries held high-level talks about the region was in 1977.

State Department officials have insisted that the meeting was intended chiefly to provide an exchange of views about respective Middle East policies and not to engage in actual negotiations that could lead to superpower cooperation in a new peace conference.

But speculation about fresh diplomatic gambits has grown recently following completion of the first part of a three-stage Israeli troop withdrawal from Lebanon, a visit to Washington by Saudi Arabian King Fahd and a tentative agreement between Jordan and the Palestine Liberation Organization to cooperate in peace negotiations.

Jordan's King Hussein arrived in Austria yesterday for a skiing holiday. U.S. officials denied that Murphy might meet with him here.

State Department officials said the United States wanted to use the discussions to explore Soviet views about the Arab-Israeli dispute, the Iran-Iraq war and Afghanistan.

But the United States is said to have rejected the idea of an international peace parley that is favored by Moscow. U.S. officials said Moscow must show the sincerity of its desire to play a positive role in the Middle East through such steps as restoring diplomatic ties with Israel and improving the situation of Soviet Jews.