Ankara, Turkey (Reuters): Turkey summoned the Dutch envoy in Ankara on Monday to complain about the actions of Rotterdam police against Turkish protesters over the weekend, as the row over Ankara's political campaigning abroad widened, foreign ministry sources said.

President Tayyip Erdogan, who is seeking support from Turks in a referendum on boosting his powers, has said the Netherlands is acting like a "banana republic" and should face sanctions for barring his ministers from speaking in Rotterdam.

Dutch police used dogs and water cannon on Sunday to disperse hundreds of protesters waving Turkish flags outside the consulate in Rotterdam. Some protesters threw bottles and stones and several demonstrators were beaten by police with batons, a Reuters witness said. Mounted police officers charged the crowd.

A statement attributed to ministry sources said, "The Turkish community and our citizens were subject to bad treatment, with inhumane and humiliating methods used in disproportionate intervention against people exercising their right to peaceful assembly."

The sources also stated that Turkey's foreign ministry also said it sought an official written apology for the treatment of its family minister and diplomats there.

It was the third time the Dutch charge d'affaires was summoned since Saturday over the row. The Dutch ambassador is on leave and the Turkish foreign ministry has said it does not want him to return "for some time".