Presidential spokesman Ibrahim Kalın said there is a way to defuse the tension between Europe and Turkey in an interview on Monday.

Speaking to Al Jazeera English in Istanbul, Kalın said: "The situation could improve if Europe stops appeasing right-wing extremists, harboring terrorists and refrains from further acts of aggression towards Turkey and Turkish citizens abroad."

He rejected the notion that Turkey was at fault.

"The idea that Turkey is divorcing from the European Union is also a mischaracterization of what is happening. If Europe's idea of cooperation and partnership is for their partners to do their bidding, then they should start rethinking it," he said.

Kalın's remarks come after a recent diplomatic standoff between Turkey and several European countries.

About the upcoming referendum on constitutional reforms in Turkey and the proposed transition to executive presidency, he said: "The executive presidency will help Turkish democracy defend itself against outside interventions."

"The Turkish people know why it is imperative for certain changes to become firmly institutionalized and understand that we cannot defend our democracy against attacks if we do not take certain steps right now."

Turkish voters will head for the referendum on Sunday.

A Yes win would see Turkey's constitution changed from a parliamentary model to a presidential system, giving the president wide-ranging powers and removing the office of prime minister.

Kalın rejected the criticism that the executive presidency would "establish a one-man rule" in Turkey.

"This criticism is completely unfounded. The proposed changes, if adopted, will strengthen the separation of powers, give the parliament unprecedented powers to investigate the president's actions and, if necessary, call for an early presidential election as a last resort."

About whether the referendum under a state of emergency would cause a doubt over transparency, he said: "To ensure transparency, we extended official invitations to international observers to monitor all aspects of the referendum."

"In addition to representatives from various political parties, certain non-governmental organizations are mobilizing volunteers."

He added that security operations being held in the country would not affect the ability of voters to participate in the referendum.

"As always, there was a period for voters to change their residential addresses. We do not expect any problems whatsoever," Kalın said.