Former secretary of state Henry A. Kissinger, apparently undeterred by the assertion of his former aide, Secretary of State Alexander M. Haig Jr., that the unratified U.S.-Soviet SALT II nuclear arms treaty is "dead," yesterday joined the growing list of influential public figures and lawmakers calling for revival of the pact.

In a speech in the Netherlands, Kissinger said that while President Reagan's newly revealed proposal for strategic arms reductions talks, or START, is surely on the right track, these very far-reaching proposals could be "enormously time-consuming" to negotiate.

Because of this, he said that he "would lean" toward ratification of the earlier strategic arms limitation treaty, called SALT, as an interim agreement pending some modifications of that treaty.

In the Senate Armed Services Committee, where one day earlier Haig had warned SALT supporters against trying to resurrect the 1979 treaty, Sen. Gary Hart (D-Colo.) also urged the Senate to ratify SALT II because it was still "an extremely useful agreement which would enhance our national security in a number of concrete ways."

Hart is among a growing number of mostly Democratic lawmakers and officials of earlier administrations who have called for giving formal approval to the treaty signed by President Carter and Soviet President Leonid Brezhnev in 1979 but never ratified by the Senate for various reasons, including the Soviet invasion of Afghanistan late in that year.

The Reagan administration has sharply rejected the Carter-era treaty, claiming that it allows big Soviet advantages in very large land-based missiles that threaten to knock out this country's force of smaller missiles. However, the White House has continued to abide by the treaty's unratified limitations as long as Moscow does.

Yesterday, Kissinger--who served Presidents Nixon and Ford--said that while he didn't want to "re-open partisan wounds," he had "great difficulty understanding why it is safe to adhere to a nonratified agreement while it is unsafe formally to ratify what one is already observing."

The Senate panel, which is conducting hearings on control of atomic arms as concern over the issue grows in the country, also heard indirect support for SALT II yesterday from Roger C. Molander, a former specialist on nuclear weapons and arms control on the White House National Security Council staff in the Nixon, Ford and Carter administrations.

Molander is executive director of "Ground Zero," a nationwide organization that sees itself as an educational help to the public on such issues without advocating specific solutions.

Molander, in his statement to the committee, did not take direct sides on the three alternatives now facing the nation--Reagan's START plan, Carter's SALT II and the various nuclear "freeze" movements. But he made essentially the same point as Kissinger: that the president's plan is far-reaching and likely to be time-consuming at a time when "the American people are anxious to see concrete results."

SALT II, Molander said, would be a modest interim step that "freezes the competition in about 10 different areas and slows it down in several others." He recalled that the Joint Chiefs of Staff, the nation's military leaders, described the pact as "modest but useful."

Molander and Rep. Albert Gore Jr. (D-Tenn.), sponsor of an alternative arms control plan that has attracted considerable interest, warned yesterday that even at the sharply reduced levels of missiles and warheads proposed by the president, "each side would still be in a position to launch a first strike against the other's ICBMs land-based missiles , while retaining a substantial force in reserve," as Gore put it.

Although the Senate committee has provided a forum for many critics of the president's plan, it also was the setting yesterday for an endorsement of what is probably the political reality. Sens. Henry M. Jackson (D-Wash.) and John W. Warner (R-Va.) spoke in support of their nuclear arms control resolution, which is exactly what the president proposes. And, as noted by committee Chairman Charles H. Percy (R-Ill.), the Jackson-Warner resolution has 60 cosponsors, almost two-thirds of the Senate.