British Prime Minister David Cameron urged the international community on Monday to send more aid to Syrian refugees in host countries in the Middle East, as a way of stemming mass migration to Europe.

Cameron made the comments during a tour of Jordan's sprawling Zaatari refugee camp, which is home to more than 80,000 Syrians.

More than 4 million Syrians have fled to Jordan, Lebanon, Turkey, Iraq and Egypt since the conflict in their homeland erupted in 2011.

With the crisis dragging on, U.N. agencies, including the World Food Program, have faced growing funding gaps, prompting sharp cutbacks in food and cash aid to refugees in the region's host countries.

Aid officials say this loss of support has helped fuel attempts by growing numbers of refugees to reach Europe.

Cameron said Britain has given about >1 billion ($1.53 billion) to the region so far.

"I would encourage others to step up to the plate and spend and invest in the way Britain has done," he said.

The British leader said helping the refugees is a moral imperative, but that "there is also a real connection to the refugee crisis in Europe."

He noted that millions have been displaced by the Syria conflict. "There is an enormous number who could decide to come to Europe," he said. "That underlines the importance of other countries supporting the refugee camps and supporting people who remain in Syria."

European leaders are at odds over how to handle the mass influx to Europe of refugees, many of them Syrians. At a meeting in Brussels on Monday, the EU's interior ministers were discussing how to share 160,000 asylum seekers among the bloc's 28 nations.

Cameron has said the scheme would encourage more refugees to try to reach Europe in sometimes fatal journeys across the Mediterranean Sea.

Britain has agreed to resettle 20,000 Syrian refugees from camps over the next five years.

Earlier Monday, Cameron met in Beirut with his Lebanese counterpart, Tammam Salam, and visited an encampment of Syrian refugees in the eastern Bekaa Valley, close to the Syrian border.

"This morning I was in the Bekaa Valley to see for myself that (Lebanese) hospitality and meeting with some of the Syrian refugees that we will resettle in the United Kingdom," Cameron told reporters in Beirut.

Lebanon hosts more than 1.1 million Syrian refugees- equivalent to a quarter of the country's entire population.

"The refugee crisis that today has reached the heart of Europe is a phenomenon that will not stop expanding unless a political solution is reached that stops the war in Syria," Salam said.

The extremist Islamic State group controls nearly half of Syria, more than four years after the start of an uprising against Syrian President Bashar Assad. The militant group has also seized large areas of Iraq.

Cameron said Britain, which has already trained over 5,000 Lebanese soldiers and helped build a series of watch towers on the border with Syria, would continue to help defend Lebanon from IS, which holds territory just 60 miles (100 kilometers) from the Lebanon-Syria border.