Relations between US and Mozambique, once cool, are getting warmer

Mozambican President Samora Machel's visit to Washington points to a steady improvement in relations with the United States. The leader of this avowedly Marxist nation is eager, observers say, to establish a rapport with President Reagan, whom he is scheduled to meet tomorrow.

Increasing private American investment in Mozambique is one of Machel's main goals. He is expected to stress that his country welcomes US private enterprise and to publicize Mozambique's new, liberal foreign investment code.

Machel's advocacy of closer ties falls on sympathetic ears at the State Department. It is thanks to Machel that the Reagan administration has something to show for its ``constructive engagement'' policy in southern Africa. (The policy consists of using quiet diplomacy to bring about change in South Africa's policy of apartheid and at improving ties between South Africa and its neighbors.)

The 1984 Nkomati nonaggression accord between South Africa and Mozambique, which the US encouraged, was considered a historic achievement and a model for improved regional relations. Although the treaty, in which both sides promised to stop supporting each other's internal opposition, has failed to mitigate rebel activity inside Mozambique, the US and Mozambique both feel it would be counterproductive to abandon it. Both need to make the Nkomati Accord yield dividends: Machel because he inve sted much personal prestige in it, and Washington for the sake of constructive engagement.

The US Congress is likely to be Machel's least receptive audience. The Reagan administration and the Mozambican government were surprised at the vehemence with which the House and Senate objected to US involvement with Mozambique during debate on the 1986 foreign aid bill. An administration proposal to provide $3 million in ``nonlethal'' military assistance in Mozambique's aid package passed, but only after strong opposition. An amendment making all nonemergency aid conditional on holding free elections

and reducing Soviet military presence in the country was removed from the bill's final version only after insistent administration lobbying.

However, there is still solid Congressional opposition to the Machel government. The rebel Mozambique National Resistance has articulate representation in the US and powerful backers in Congress. If the Reagan administration is to have a free hand in increasing US aid to Mozambique, Machel will need to make his case against the rebels and overcome congressional opposition to closer economic and military ties, analysts say.

Machel would like to reduce his military dependence on the Soviets. In scheduled meetings with congressmen, observers say Machel plans to push the message that -- Russian military advisers notwithstanding -- his government is not beholden to the Soviets. More difficult will be to convince skeptical legislators that the rebels are simply South African-backed terrorists without internal support, as the government claims.

Not long ago Mozambique and the US were at cross-purposes.

The first years after independence from Portugal in 1975 were marked by a pronounced partiality toward the East bloc. The US had supported Portugal, a NATO ally, against the Frelimo (Front for the Liberation of Mozambique) guerrillas. Once in power, Frelimo declared Mozambique a Marxist-Leninist state. This, along with anxiety about the possible concession of a naval base to the Soviet Union, raised tensions with the US. Relations reached their low point with the expulsion of four US diplomats from Moza mbique in 1981 on charges of spying.

Ties began improving after drought struck that same year. Mozambique's East Bloc allies could spare little food and the majority of aid came from the West. US aid has increased steadily since the drought began and will reach 160,000 tons of food this year alone, in addition to agricultural and transport assistance.