Dutch Foreign Minister Bert Koenders has warned the Netherlands cannot guarantee the safety of citizens travelling to Turkey if they have been critical of Turkish leaders.

Dutch Foreign Minister Bert Koenders has warned the Netherlands cannot guarantee the safety of citizens travelling to Turkey if they have been critical of Turkish leaders.

The warning, made during a parliamentary debate on Tuesday, comes as the Dutch government is working to lift a travel ban on Dutch-Turkish journalist Ebru Umar who was briefly arrested over the weekend for tweeting comments critical of President Recep Tayyip Erdogan.

Umar, a well-known Dutch feminist journalist of Turkish origin, said she was hauled out of bed and arrested late Saturday at her home in Kusadasi, a resort town in western Turkey.

She was released on Sunday after being questioned for 16 hours as top Dutch officials raised their concerns with their Turkish counterparts. But she is not allowed to leave the country and must report to police twice a week.

Koenders said the government was being "very active" on Umar's case and "hoped she may return home soon."

But asked Tuesday in the Dutch parliament if he could provide guarantees for Dutch or Dutch-Turkish citizens travelling to Turkey on holiday who may have criticized Erdogan on social media, he said "no".

"There are no guarantees," Koenders insisted.

"We have just had a case showing exactly what can happen. That is why we are working on it. But I cannot give any guarantees."

He also delivered a sharp warning to Turkey that "if it wants to step closer to Europe, it must significantly improve its behavior."

"Let's be honest. You can't treat the press and press freedom this way, if you want to be part of Europe."

Umar's treatment has sparked anger in The Netherlands, and she tweeted out a new video message of thanks Wednesday for the "heartwarming" support.

On Monday, the daily De Telegraaf published a large front page cartoon entitled "The long arm of Erdogan" depicting an ape with the Turkish leader's face crushing a woman resembling Umar.

Trials in Turkey for insulting Erdogan have multiplied since his election to the presidency in August 2014, with nearly 2,000 such cases currently open.