The Defence Secretary, Sir Michael Fallon, has chaired another meeting of the emergency COBRA committee to discuss Britain's relief operation in the Caribbean, following the devastation caused by Hurricane Irma.
500 troops have now been deployed. The MoD says RAF aircraft have carried Royal Marines, as well as Engineers and specialist personnel from all three services to the region.
Sir Michael Fallon says regular military aid flights will be continuing.
The move follows criticism that the response to helping British Overseas Territories had been too slow.
The Royal Navy’s flagship HMS Ocean is also joining the relief effort, having been diverted from deployment in the Mediterranean.
It could take her up to two weeks to arrive, but she carries Puma helicopters, as well as engineers, Royal Marines and medical advisers.
The Ministry of Defence told Forces News that the UK would send a military task group to the Caribbean where Hurricane Irma has hit several islands.
The storm has left more than a dozen people dead and made thousands homeless, with St Martin and Barbuda particularly badly hit.
The Defence Secretary Sir Michael Fallon said: "In the face of such devastation, I have authorised the deployment of a task group to the region.
"Over the next 24 hours troops and engineers held at high readiness in the UK will deploy with helicopters to support the relief effort. I am also sending a command headquarters to co-ordinate our efforts.
"With the danger posed by Hurricane Jose which will hit areas already affected by the storms we are diverting a second ship to the Caribbean, our flagship HMS Ocean, to bring the help that will be needed in reconstruction after the hurricanes has passed."
Last week, HMS Ocean departed Plymouth to spend the next few months in the Mediterranean on NATO operations before she is decommissioned next year.
She will be replaced by the far larger Queen Elizabeth aircraft carrier in 2020.