The head of the U.N. refugee agency in Jordan says donor countries chose the "cheap option" by failing to provide sufficient aid in the Syria crisis and now face consequences such as growing migration to Europe.

Andrew Harper told The Associated Press it would have been more cost-effective for the international community to spend more money in countries next to Syria, such as Jordan and Lebanon, where more than 4 million refugees found asylum.

Cash-strapped aid agencies have been forced to cut back support for desperate refugees in these countries, and more are now trying to reach Europe.

Harper said Wednesday that Europe, the Gulf states and others "sought the cheap option which was to provide us with peanuts in order to deal with the worst humanitarian situation for decades."