Voters in the French territory of New Caledonia in the south Pacific have narrowly rejected – for a second time – a proposal to break away from Paris, choosing to remain loyal to the French republic in a nationwide referendum. But campaigners for secession say the struggle for independence will go on.

As it had in 2018, the “no” vote for independence prevailed, this time 53.3% to 46.7%, according to unofficial results declared by the French president, Emmanuel Macron.

But a significantly improved “yes” vote, up from 43% last referendum and now approaching the simple majority needed for secession, has given a massive fillip to the independence campaign, and laid the foundations for a third and final referendum on the question in two years’ time.

The push for independence – overwhelmingly supported by New Caledonia’s indigenous Kanak population, who make up about 40% of the population – now appears a real possibility for 2022.

“The path to independence and sovereignty is inevitable,” the coalition of independence parties – the Front de Libération Nationale Kanak et Socialiste (FLNKS) – promised in the run-up to Sunday’s poll, and, despite their defeat, its leaders argue they will continue the campaign for secession.

Roch Wamytan, the speaker of New Caledonia’s Congress and a veteran member of the largest independence party, Union Calédonienne, said the campaign would continue to the next referendum, and potentially beyond.

“If the ‘no’ wins again in two years, we’ll get together, we’ll talk, and we’ll figure something out.”

In a televised address, Macron said “a third referendum is possible … It’s up to your congressmen to decide. The state, true to its word, stands ready to organise it if that is their choice.”

First colonised by France in 1853, the islands of New Caledonia – just 1,500km off the coast of Australia – remain a French colonial dependency.

Sunday’s poll was the second of potentially three national referendums agreed under the 1998 Nouméa Accord, a carefully negotiated de-colonisation plan brokered to end a deadly conflict between the mostly pro-independence Kanak population and the descendants of European settlers, known as Caldoches, in the 1980s.

That violence culminated in a bloody, drawn-out hostage crisis in 1988 that saw 19 separatists killed on one side, and six police and special forces soldiers on the other.

While the yes/no divide is regularly cast as a contest between separatist Kanaks and loyalist Europeans, New Caledonia’s 180,000-strong voting roll also includes descendants of indentured Indochinese labourers, as well as more recent migrants from France, Wallis and Futuna, Vanuatu and other French dependencies.

A third referendum can be held within two years if a third of the local assembly votes in favour of it.

New Caledonia has largely avoided the coronavirus pandemic: just 27 cases and zero deaths have been recorded since the pandemic began. With no community transmission of the virus, 294 polling stations were able to open for regular voting across the country at 8am on Sunday.

Turnout was significantly higher than the previous referendum in 2018, with long queues being reported from most districts. New voters came to the polls for both yes and no: yes voters who were urged to boycott last time by some leftwing parties and trade unions, and no voters who had been convinced of an easy victory in 2018.

In the early afternoon, supporters of independence danced jubilantly on the streets of Nouméa, sounding car horns and waving hundreds of Kanaky flags of independence, almost as if celebrating a victory.

“I’m sure we’ll make it; we have suffered enough for the past 30 years,” Germain Tokotoko said.

“I’m from Ouvéa, the island where the cave assault happened [when 12 independence supporters were killed by the French army in May 1988]. That’s why I’m for the return of the custom, the freedom of my country, and the independence of my government.”

Loyalists say they fear for the character of the country, as well as its economic future.

From more than 10,000 miles (16,000km) away, the French government subsidises the territory with approximately €1.5bn (£1.3bn) every year, the equivalent of more than 15% of New Caledonia’s GDP.

“I am French and I want to remain French in the future,” says 19-year-old voter Kevin, a resident of the rural commune La Foa, but registered to vote in the capital. “If the ‘yes’ passes, today or in two years, I don’t know what will become of us.”

At the close of polls, the Union Calédonienne president, Daniel Goa, welcomed the high voter turnout and said he “strongly calls on each citizen not to be overwhelmed by emotions and to welcome the result in a peaceful atmosphere”.