Violence ripping Sri Lanka at seams; Jayewardene tackles Tamil problem with committees and Israeli advisers

''I don't consider the Tamil problem a problem. It's a disaster.'' So said Sri Lankan President Junius Richard Jayewardene after visits to Washington, London, and New Delhi, where Sri Lanka's increasingly separatist Tamils were very much on his mind.

He reportedly urged President Reagan and Prime Minister Margaret Thatcher to curb the activities of militant Tamils in Britain and the United States. He claims that these militants are raising money and buying arms for Tamil extremists, known as the ''Tamil Tigers,'' who operate between the south of India and Sri Lanka's northern Jaffna peninsula, where they want to establish a visionary Tamil nation which they call ''Eelam.''

With India's Prime Minister Indira Gandhi - in whose southern state of Tamil Nadu the ''Tigers'' have set up command structures and guerrilla training centers along the porous Coromandel Coast - the President was said to have been even more emphatic. He reportedly asked for the extradition of 16 top ''Tiger'' leaders, including those who masterminded the kidnapping of an American couple in Jaffna in May.

Mrs. Gandhi reportedly responded by not responding. She also expressed her own concern at Mr. Jayewardene's decision to hire former members of the elite British commando organization, the Special Air Service, and active members of the Israeli intelligence organization, Mossad, to set up a Sri Lankan intelligence organization and train a paramilitary force.

''We will get help from the devil himself if necessary,'' the Sri Lankan leader told a press conference on May 31, when referring to his controversial decision to seek security assistance from the Israeli Mossad.

The Israelis have now set up a ''special interests section'' in Sri Lanka under the auspices of the US Embassy. It is the first time the Americans have acted in such a capacity for the Israelis anywhere in the world. And it is a stepping stone toward the reestablishment of diplomatic relations with Israel, suspended by the government of Sirimavo Bandaranaike 14 years ago.

Reacting to Mr. Jayewardene's decision to seek Israeli assistance, the country's Muslims have staged fierce riots. And the ''Tamil Tigers'' vow they will eliminate the ''Zionist threat.''

This once-tranquil, lush island, known to explorers as ''Serendip,'' runs the risk of being pulled apart at its very seams. The President himself has described Sri Lanka as ''the Northern Ireland of the Indian Ocean.'' It is hard to find anyone on the island who would challenge the President on this.

Relations between Sri Lanka's 2.6 million Tamils, most of whom are Hindu, and its 11 million, generally Buddhist, Sinhalese have been strained since the country became independent from Britain in 1948. Last July tension turned to savagery in anti-Tamil rioting that claimed hundreds of lives. Thousands were left homeless. The largely Tamil economy of the capital was turned upside down. Factories and offices were gutted. Potential foreign investors packed their bags and fled.

''The problem,'' said a Western diplomatic official who is normally sympathetic to President Jayewardene, ''is that the government persists in looking at the Tamil problem as a terrorist problem and not a communal problem.

''There are 21/2 million Tamils in this country. At the very most, 5,000 have joined the 'Tigers' and are capable of raising arms. But the longer the government procrastinates and refuses to listen to legitimate Tamil demands, the more attractive the 'Tigers' become, and the more militant even a simple Tamil housewife will inevitably become.''

An all-party conference launched with much fanfare in January to negotiate Sri Lanka out of its Tamil impasse floundered, was boycotted, and finally disintegrated in May. The President now claims he is armed with a new set of proposals to revive the moribund talks. If the Tamils do not accept them, he may hold a referendum before the end of the year.

Meanwhile, committees have been set up to ''examine'' Tamil grievances on education, employment, and language, plus a more important committee to discuss how powers would be devolved to local government bodies, a key Tamil demand. But , in the words of a worried Sinhalese government official, who scorns the country's rigid Buddhist priests, ''Once you put something into committee in South Asia, that is its last breath of life.''

It was in fact the Buddhist clergy that rejected a compromise formula arrived at after painstaking negotiations between India and Sri Lanka late last year. The compromise proposed devolution to regional councils.

With 50 million electorally vital Tamils in the south of India, the government of Mrs. Gandhi has taken a keen interest in a negotiated settlement to Sri Lanka's Tamil morass. Regional councils were quite acceptable to the moderate leadership of the Tamil political party, the Tamil United Liberation Front, yet the proposals were never brought before the conference by Mr. Jayewardene.

The Buddhist priests, always an active behind-the-scenes ingredient in Sri Lanka's body politic, have been emboldened to come to the forefront since the riots last July. Regional councils would grant too much autonomy, they argued. And President Jayewardene has admitted quite candidly that he would lose the political support of the island's 75 percent Sinhalese voters if he conceded too many of the Tamil demands.

Thus, wherever one ventures on this sun-drenched island, from waiters to taxi drivers, boutique owners to Tamil militants, there is the overriding impression that yet more violence is to be expected in the land of ''Serendip.''

Political uncertainty has led to a drop in tourist arrivals of nearly 30 percent. Inflation is surging upward at an estimated 20 percent.

Potential Western investors, many of them American, who were caught up in the last summer's mayhem have not returned.

The rather bleak scenario has led some Western sources to say that the real victim of last summer's riots was Mr. Jayawardene.