Turkish Prime Minister, Recep Tayyip Erdogan, has said plans to redevelop a park in Istanbul will go ahead despite mass protests rocking the country, BBC reports.
Describing some of the protesters as "extremists", he said seven foreigners had been arrested over the unrest.
Erdogan made the remarks in Tunis. He is to return to Turkey from a North African tour later on Thursday.
A large protest group has called for further demonstrations in response to the comments, correspondents say.
The demonstrators had hoped for a sign of compromise from the prime minister.
But Erdogan's comments are likely to fan the flames, as Turkey's worst unrest in decades looks set to build yet further, our correspondent says.
The economic response was swift, with the stock market dropping nearly five per cent after the prime minister's announcement.
The original sit-in at Gezi Park spiralled into nationwide unrest after police cracked down on activists defending the green space near Istanbul's Taksim Square from developers.
For days, demonstrators in Istanbul, Ankara and other cities have been calling for the three-term prime minister to quit.
They accuse Erdogan's government of becoming increasingly authoritarian and trying to impose conservative Islamic values on a secular state.
Four people are reported to have died, thousands have been injured and hundreds arrested in the unrest.
Speaking in Tunis, Erdogan said a small group of extremists was manipulating what had started as an environmental protest.
"Among the protesters, there are extremists, some of them implicated in terrorism," he told reporters.
Erdogan also defended the urban development plan for Gezi Park, which is near Istanbul's Taksim Square.
"The project respects [Turkey's] history, culture and environment," he said.
"What we are doing is to protect the rights of the majority and to preserve the beauty of Istanbul."
Tunisian riot police surrounded the Turkish embassy in Tunis during Erdogan's visit, after local left-wing groups called for protests to show solidarity with the demonstrators in Turkey, the AP news agency reports.
Before leaving for his official tour of North Africa on Monday, Erdogan had predicted the protests would be over by the time he came home.
But on the eve of his return, police in the capital Ankara used tear gas and water cannon on protesters who had erected barricades and set them on fire. Rioting was also reported in the city of Tunceli.
The Punch
The protests make sense to me if I'm asked. Such things have to happen for things to be fine with everyone.