SYDNEY (Reuters) -A thousand police arrived in New Caledonia from France and streets were relatively calm, the French High Commission said on Monday, but roads were blocked and the airport remained shut, stranding tourists on the Pacific island after a week of riots.

The activist group organising the protests in the French-ruled territory, Field Action Co-ordination Cell (CCAT), said in a statement on Monday blockades would continue, urging protestors to use a peaceful approach.

Road blocks were making it difficult to supply food to stores in several areas and provide secure travel for medical staff, New Caledonia government officials said.

"It's important to point out that the problem is not so much a lack of staff, medical and food supplies but more importantly an access problem," a government statement said.

Australia's Prime Minister Anthony Albanese said "the situation there is deeply concerning", after night when there was fire and looting.

France's top official in the territory, Louis Le Franc, said on Sunday evening a police operation to regain control of the road from the capital Noumea to the international airport would take several days. Gendarmes had dismantled 76 road blocks.

Albanese told ABC radio that Australia had been seeking approval from French authorities for two days to send an evacuation flight to New Caledonia to pick up tourists stranded in hotels.

Around 300 Australians have registered with consular officials in the French territory, which lies in the southwest Pacific, some 1,500 km (930 miles) east of Australia.

"The international airport remains closed, roads have been damaged, there are blockades in place," Albanese said.

"We continue to pursue approvals because the Australian Defence Force is ready to fly when it's permitted to do so," he added.

There are around 3,200 people stuck waiting to leave or enter New Caledonia as commercial flights have been cancelled due to the unrest that broke out last week, the local government said.

New Zealand defence aircraft were also on standby to bring New Zealand nationals home, New Zealand's Foreign Minister Winston Peters said.

"We are ready to fly, and await approval from French authorities as to when our flights are safe to proceed," he wrote on social media platform X on Sunday.

Protests erupted last week sparked by anger among indigenous Kanak people over a constitutional amendment approved in France that will change who is allowed to participate in elections, which local leaders fear will dilute the Kanak vote.

Six people have been killed and the unrest has left a trail of burnt businesses, torched cars, looted shops, and road barricades, cutting off access to medicine and food.

Three of those killed were indigenous Kanak youths and two were police officers. A sixth person was killed on Saturday during a gun battle between two groups at a roadblock, French police said.

The business chamber said 150 companies had been looted and burnt.

Pro-independence political parties said they want the French government to withdraw the electoral reform before they restart talks.

(Reporting by Kirsty Needham in Sydney and Lucy Craymer in Wellington; Editing by Sonali Paul)

By Kirsty Needham