The Pentagon announced yesterday that it intends to sell Israel 200 improved Hawk mobile antiaircraft missiles--a move that could make it easier to get Congress to approve the sale of the same weapons to Jordan.

The proposed sale to Israel, which must be reviewed by Congress, would cost that country $47 million. The Defense Department said the missiles would "supplement" Israel's current supply, "ensuring an adequate war reserve and adequate missiles for annual training requirements."

At a National Press Club appearance yesterday, Defense Secretary Caspar W. Weinberger stuck by his earlier assertions that Jordan needs antiaircraft weapons that are better than the old Hawks, which are bolted to cement pads in that country. "Immobile antiaircraft is not very useful," he said, adding that no one has "quarreled with that viewpoint" from a military standpoint.

Defense specialists from the United States and Jordan are scheduled to meet April 28-29 in Amman to discuss the kingdom's defense needs. Francis J. West Jr., an assistant secretary of defense, will head the U.S. delegation.

Pentagon officials said the Hawk sale to Israel was in the works before Weinberger's visit to Jordan last month, but agreed that the deal might ease the way for selling the improved Hawk mobile missiles to Amman.