President Reagan launches an effort to smooth relations with Congress as he pursues tax reform and deficit reduction. His efforts must be played out against a background of lackluster growth in the US economy. Reagan seeks peace with Congress as tax and deficit votes loom

Determined to take the offensive as he begins his sixth year in office, President Reagan is pursuing a strategy designed to smooth relations with Congress and court public support for his second-term agenda: The President is fast off the mark meeting with GOP congressional leaders to press his legislative goals and clear away any strains lingering from the last session of Congress. Later this month he will probably drop in on a session of the House Republican Conference on Capitol Hill, a White House aide says.

Mr. Reagan will deliver a State of the Union message on Jan. 28 which forgoes the usual ``laundry list'' of presidential objectives in favor of a shorter, more thematic speech that stresses his vision for the future.

The White House is stepping up its legislative operation to ensure more effective liaison with lawmakers. White House chief of staff Donald T. Regan has already met with House GOP leaders to talk about better communication. More meetings with small groups of legislators are planned, and Mr. Regan and other White House officials will attend the House GOP meeting on Jan. 31.

With a legislative struggle looming over the fiscal 1987STRATEGYSTRATEGY budget, the President is trying to smooth the way with GOP lawmakers even while keeping pressure on them to hold the line on taxes and defense. In a breakfast meeting with 47 Republican senators Wednesday, he repeated his strong opposition to any tax increase and his support for a 3 percent increase in defense spending as essential to progress in the Geneva arms talks.

On Capitol Hill, many Democrats and Republicans, including Senate Budget Committee chairman Pete V. Domenici (R) of New Mexico, forecast a presidential compromise on taxes before the budget process plays itself out. But Senate Finance Committee chairman Bob Packwood (R) of Oregon says he expects a ``a gigantic money package'' to emerge from Congress without any new taxes.

``There will be no new taxes even whispered without the President taking the lead,'' Senator Packwood told reporters yesterday. And Reagan can get a budget without taxes, he says.

Mr. Packwood sketches a scenario that avoids triggering automatic cuts under the new Gramm-Rudman-Hollings budget-balancing law. By April, he says, a legislative stalemate will develop over the budget because of the President's promised vetoes of certain spending bills. This will lead to a bipartisan meeting between congressional leaders and key administration officials aimed at reaching a consensus -- without taxes -- on how to achieve the $144 billion deficit target for 1987.

Packwood also predicts that his committee will have a tax-reform bill ready for Senate consideration after the Easter recess. In this connection the President, in his meeting with Republican senators, said he would like the Senate to restore elements which the House removed from his original tax package, including elimination of deductibility for state and local taxes.

As the President lays down his positions on the budget and other issues, a major challenge for his aides is to improve communication with Congress, especially members of his own party, to avert the tensions that almost defeated Mr. Reagan's tax-reform initiative last year. Then the President ran into trouble with Senate Republicans when he first indicated support for a budget cut in social security cost-of-living adjustments and subsequently reversed himself.

Later in the year, House Republicans broke ranks when the White House initially ignored congressional concerns about the tax-reform bill moving through the Democratic-led House Ways and Means Committee. The President had to mend fences on the Hill and compromise before Republicans rescued the tax-reform package.

White House officials say the tensions with Congress last year were no different from those over the tax bill in 1982. But there is clearly a concerted effort to start off on the right foot as Congress gets under way. ``The leadership in the House and Senate are in a very cooperative mood, and so are we,'' a key aide says. ``We realize that working together we can get more done.''