Jordan's King Abdullah says his country needs long-term aid from the international community to cope with a huge influx of Syrian refugees, warning that unless it received support the "dam is going to burst".

King Abdullah said the refugee crisis was overloading Jordan's social services and threatening regional stability.

Jordan has already accepted more than 600,000 UN-registered Syrian refugees.

"Jordanians are suffering from trying to find jobs, the pressure on infrastructure and for the government, it has hurt us when it comes to the educational system, our healthcare. Sooner or later I think the dam is going to burst," King Abdullah said. 

Last Thursday, officials said the European Union would promise some €2bn at an international donor conference to be held in London this week to aid Syrian refugees in Jordan, Lebanon and Iraq.

British Prime Minister David Cameron said last month he would press the EU to relax export rules for Jordan, to help spur economic growth.

"This week is going to be very important for Jordanians to see is there going to be help not only for Syrian refugees but for their own future as well," King Abdullah said.

Part of the US-led coalition that is bombing Syria, Jordan has long been praised for helping refugees and has been a big beneficiary of foreign aid as a result.

However, it has drawn criticism from western allies and the UN High Commissioner for Refugees over the situation near its border with Syria, where thousands of refugees are being kept far from any aid.

The situation has deteriorated since Russia started airstrikes last September to support President Bashar al-Assad.

King Abdullah said if Jordan was not helped, the refugee crisis would worsen.

"The international community, we've always stood shoulder to shoulder by your side. We're now asking for your help, you can't say no this time," he said.