Mitterrand's caution over Pacific colony angers all sides

As tensions continue to boil in the far-off island paradise of New Caledonia, French President Francois Mitterrand faces a difficult task reconciling opposing factions - both in the Pacific and in Paris.

The first problem is the escalating violence in the territory. Melanesian militants have killed a white settler and have been constructing roadblocks and burning the houses of French settlers. The whites have responded by killing one native and forming their own roadblocks.

Back in France, TV pictures of fleeing whites have sparked an emotional response among a population with vivid memories of past colonial traumas in Vietnam and Algeria. Combined with the botched withdrawal from Chad, Mr. Mitterrand has been plagued by charges of weak leadership - helping to pull his poll ratings down to an all-time low of 25 percent.

In a parliamentary debate Tuesday on New Caledonia, the opposition attacked Mitterrand again. ''The government must reestablish order,'' said former Defense Minister Pierre Messmer, a Gaullist.

Instead, Mitterrand has reacted cautiously. He has reinforced the island's contingent of gendarmes but has not ordered it to take forceful action to stop the violence.

The President hopes to reach a negotiated settlement. He named Edgard Pisani as high commissioner for the territory, and instructed him to prepare a set of recommendations within two months for a referendum on self-determination.

Most native Melanesians want independence, and most French settlers want o keep their ties with Paris.

In France, the debate similarly splits the population. Traditionally the Socialist and Communist left has supported independence, arguing that France must stop destroying the native culture. In the 1981 campaign, Mitterrand promised early independence, only to propose later a referendum on self-determination for 1989.

In principle, conservatives accept the notion of such a referendum. But they worry about an Algeria-style sellout of the island's white settlers. The government feels caught between these two positions.

''We cannot, as some wish, act as if the independists did not exist, and we cannot, as some wish, pretend that the settlers don't exist,'' said Prime Minister Laurent Fabius in the parliamentary debate. ''It's within this contradictory situation that we must construct a path.''

The government has reportedly instructed High Commissioner Pisani to work on three possible scenarios:

* The 1989 referendum could be kept. But the native militants fear that this plan would be scrapped if the Socialists lose power in France in 1986.

* These worries could be appeased by bringing the referendum forward perhaps to next year. But the conservatives on the island and in Paris complain that this would cancel the win by the settlers in last month's territorial election. The Melanesians boycotted the election.

* If no consensus can be reached, the territory could be divided into two separately run communities. But the tragedies of Cyprus, Lebanon, and Ireland suggest that this solution would not solve the racial problem either.