(AFP) - France is to put off easing a coronavirus lockdown in its Indian Ocean island territory of Mayotte over concerns about the continued spread of the virus there and a fragile health system, Prime Minister Edouard Philippe said Monday.

Mainland France is due from next week to enjoy an easing of the lockdown measures imposed since mid-March to slow the spread of the coronavirus.

But addressing France's upper house, Philippe said this would not apply to Mayotte, one of France's overseas territories worst hit by the coronavirus.

There has been considerable concern in Paris about the risk of the virus to all of France's overseas territories. Philippe also said an arrival ban would be maintained in all territories for now.

"We have decided to put off ending the confinement in Mayotte," said Philippe, adding that the situation would be reassessed next week.

"Continuing the confinement is the only way to avoid a saturation of a hospital system already under pressure due to the dengue fever outbreak," he added.

Dengue fever is a mosquito-borne tropical disease that has long been a seasonal health scourge in the area and is not linked to the coronavirus.

Mayotte, a small island north of Madagascar off east Africa, is France's poorest department and has a high population density with many people living in shanty towns with poor sanitary conditions.

The island, which has a population of about 280,000, has registered eight deaths from the coronavirus, according to the French health ministry.

Of 38 COVID-19 patients in hospital, six are in intensive care.

© Agence France-Presse