The European firefighting fleet has been reduced to just five ships, as more than half the fleet is under orders to deploy, a senior European fire chief said Friday.

The fleet has to deploy and react to the unprecedented situation at a time when it is in desperate need of emergency fuel, the chief of the European fire service told reporters.

The crisis has forced the European Union to declare a state of emergency for six months.

The firefighting force has been operating under a different, non-emergency command and the fleet will be reduced to three ships in the coming days, the top European fire official said.

The three-ship rescue operation is expected to be launched later in the week, with more ships arriving from other countries in the next few days.

The rescue operation will include more than 100 aircraft, helicopters, ships and other assets, the fire official told reporters in Brussels.

The operation will be focused on the eastern Mediterranean, with the EU fire service deploying more than 150 aircraft to the region.

The European fire services are under pressure from a number of factors.

There are growing concerns that the European Maritime Safety Agency, an EU agency, is understaffed.

The European Commission has called for an overhaul of the EU’s rules of engagement, which are meant to help protect the ships and personnel of the emergency services.

The new rules, due to come into force this summer, are expected to reduce the number of emergency response aircraft from at least 12 to six.