The bow-and-arrow rebellion in the New Hebrides Islands in the South Pacific has escalated into a serious diplomatic quarrel between Britain and France, whose uneasy, 74-year-old arrangement for joint colonial rule of the islands was one of the elements in the unrest.

French officials said today they doubted the islands could be granted independence on July 30, when an already elected government of Anglo-phone New Hebridians was to assume power.

The French government cited the continuing revolt on the island of Espiritu Santo by loincloth-clad warriors backed by French planters, and the unrest on the island of Tanna in which a Francophone New Hebridian politician was shot to death last week.

France has backed out of an apparent agreement with Britian to end the uprisings with a small show of force in the capital of Vila on Efata, roughly midway between Espiritu Santo and Tanna at opposite ends of the chain of 73 islands.

A contingent of 55 Garde Mobile riot police from French-ruled New Caledonia were pulled out of Vila on orders from Paris less than 24 hours after their arrival there last week. The French government then issued a strong diplomatic protest about the arrival over the weekend of 200 British Royal Marine commandos, who were airlifted from England with arms, jeeps and other equipment.

Irritated British officials said they were "mystified" by the French attitude. They said they thought the military moves and commitment to granting independence on July 30 had been agreed in repeated negotiations between British and French diplomats and confirmed by British Prime Minister Margaret Thatcher and French President Valery Giscard d'Estaing during the European Community summit in Venice last week.

"I must confess I have been rather puzzled by what has happened," British Foreign Secretary Lord Carrington said today.

He promised to arrange still another meeting between British and French diplomats after The Times of London declared this morning that "the New Hebrides affair is no longer trivial and it is time it was dealt with on both the British and French side, with a greater sense of importance."

Meanwhile, the chief minister of the elected New Hebrides government, Walter Lini, announced that his provisional government would make one last attempt to negotiate an end to the uprisings on Espiritu Santo and Tanna before he insisted the Britain and France use force. Peace missions led by members of his government from each of the rebellious islands were named by a spokesman for Lini in Vila today.

The revolts on both islands have been led by tribal chiefs with no allegiance to either the French or the British. Jimmy Stephens, leader of the takeover of Espiritu Santo, is a bearded, Eurasian former bulldozer driver who has agitated for independence for years. He attracted the backing of the island's French planters and a group of right-wing Americans who wanted to help set up a separate, independent Espiritu Santo as a tax haven.

The uprising on Tanna appears to be the latest of several by an indigenous rebel group of "cargo cultists" who once worshipped military cargo planes that crashed there during South Pacific battles of World War II.

But these native rebels have become caught up in the traditional antagonism between Britain and France that has characterized their joint rule of the New Hebrides, with competing British and French legal systems, schools and political parties.The French fear the interests of the Francophone minority will suffer under the elected Anglophone government after independence.

"We want the territory to remain united after independence," a French Ministry of Overseas Territories spokesman said in Paris yesterday, "but this can only happen after the different minorities have had cast-iron guarantees for their rights."

The British see this as an attempt to restore French influence lost when the New Hebrides Anglophones won last November's election, which was held under United Nations supervision. The French are also believed here to fear the emergence of independence movements in their South Pacific colonies of New Caledonia, which is rich in nickel, and Polynesia, where French nuclear weapons are tested.