A new, more militant brand of Dutch labor leadership has claimed victory in its bitter wage dispute with employers and called a halt to the three-week-old national strike that crippled the world's busiest port here.

The last obstacle to a settlement was lifted Friday when dockers voted to return to work after employers agreed to grant pay increases averaging 1.8 per cent, addition to raises pegged to increases in the cost of living. Earlier, the unions had succeeded in blocking plans that would have ended cost-of-living adjustments.

Operations resumed yesterday at Rotterdam's port and at Amsterdam, which also had been affected by the strike.

Printing, transport and construction workers also reached new wage agreements with employers last week, leaving only 2,000 workers in the metal industry still on strike.

Described as the broadest outbreak of Dutch labor unrest since World War II, the strikes involved nearly 30,000 workers and caught complacent employers off guard.

Dutch labor unions are noted for their docility, and most observers felt the strikes would dissipate after the first few days. But as union leaders detonated new industrial stoppages in close coordination, the strike movement gained momentum.

The crucial boost for the union cause came in the second week, when Rotterdam longshoremen walked out and paralyzed cargo. New pressures were exerted on employers as port officials assessed losses up to $4 million a day.

The strike also became expensive for the unions, which paid compensation of $20 per day to each worker.

Some union leaders viewed the strike as a test of their political strength in a prelude to national elections in May.

Wim Kok, president of the Dutch trade-union federation, asserted that the socialist-led coalition government had backtracked in its legislative efforts to achieve greater worker participation in managerial decisions.

Dutch Prime Minister Joop Den Uyl had been accused of seeking centrist and right-wing support by adopting more moderate social policies. Many political observers feel that public opinion has grown increasingly disenchanted with the high taxes necessary to pay for the country's welfare and unemployment programs.

Labor's triumph has bolstered its sagging political fortunes, and jolted the government and employers into more acute recognition of the unions' economic clout.

Union leaders plan to press the government to revive plans for greater worker control in industry. Employers insist that key decision-making powers must remain in the hands of management.

If necessary, said an official at the giant Dutch electronics firm, Phillips, "we will take our case to the public" - hinting at a broad public relations campaign to caution the country that worker control would mean less investment, growth and employment in the future.

The government faces a treacherous path leading up the May elections. It refused to intervene in the labor dispute, and confronts a more difficult dilemma now in trying to reconcile views over worker control.

Recent polls indicate that the Social Democrats have lost ground to rightwing parties. Union officials point out that if the Social Democrats hope to win re-election in May, they will need unwavering support from the workers.

Before the strikes, labor officials were reputedly toying with the idea of boycotting the elections unless the Social Democrats reaffirmed their traditional solidarity with the unions by getting labor-backed legislation through Parliament.

Any sitting out of the election will happen now only if the Social Democrats refuse to rally labor's cause, an unlikely prospect given the renewed show of union power. But Dutch labor leaders insist that they will not feel compelled to wed labor's destiny to that of Social Democrats.

As in other West European countries, the Dutch government must contend with strong criticism over planned austerity measures - combining higher taxes with less public spending.

The Netherlands has been protected to some extent from the era of expensive oil through its vast natural gas reserves, which the country sells at prices indexed to the rising cost of oil.

But economists caution that once supplies run low, the country will face a critical balance of payments situation that could exacerbate labor troubles. Denmark, Portugal, Britain and Belgium are all experiencing nagging strikes over belt-tightening measures.

More than 300,000 workers went on strike Friday in Belgium to protest the government's austerity program, which calls for higher taxes on cigarettes, alcohol, cars and restaurants.

Train service came to a standstill and most of the country's steel industry was shut down. Belgian unions plan to enlarge the strikes over the next four weeks unless the government rescinds the proposed taxes and employers drop their opposition to a shorter work week.