The Prime Minister of Croatia has said the country will "force" Hungary to accept migrants by continuing to send them to the border.

Zoran Milanovic's statement was the latest in an increasingly bad-tempered exchange of views over how to handle the migrant influx.

Hungary has accused Croatia of breaking international law by not registering migrants - one minister reportedly calling Mr Milanovic "pathetic".

Croatia says more than 20,000 migrants have entered since Wednesday while some 8,000 passed into Hungary on Friday, the Hungarian authorities said. New busloads began arriving at the border on Saturday.

Croatia's response has typified the EU confusion over how to handle the crisis - migrants were initially welcomed to travel through the country, but then borders were hastily closed to regulate the flow as the government said numbers had become untenable.

In Hungary, migrants have at times been met with tear gas and water cannon as they try to push their way north. In Slovenia police used pepper spray on one group.

Most of the migrants, many fleeing war and poverty in the Middle East and Africa, want to go to Germany or the Scandinavian countries.