Turkish Prime Minister Recep Tayyip Erdogan has issued a " last warning " for thousands of protesters to evacuate an Istanbul park at the center of mass anti - government demos, ratcheting up tensions in two weeks of deadly unrest.

A day after meeting with protest leaders and offering to hold a referendum on plans to redevelop Gezi Park, Erdogan resumed his combative stance on the environmental protest that has morphed into the biggest challenge to his Islamic - rooted government ' s decade - long rule.

" I ' m making my last warning: mothers, fathers please withdraw your kids from there, " Erdogan said in a live television broadcast on Thursday. " Gezi Park does not belong to occupying forces. It belongs to everybody. "

Demonstrators have been camping out in the park since May 31, when police cracked down heavily on a small campaign to save the site ' s 600 trees from being razed.

The crackdown sparked an outpouring of anger across the country against Erdogan and his government, seen as increasingly authoritarian after more than a decade in power.

Erdogan inflamed tensions on Tuesday, when riot police stormed Istanbul ' s Taksim Square, the focal point of two weeks of protests, prompting a day of violent clashes with tens of thousands of protesters. The intervention fuelled fears that the adjoining Gezi Park would be cleared next.

" Don ' t sadden us anymore, let us clean Gezi park and return it to its rightful owners… the people of Istanbul, " Erdogan said, urging environmental protesters to withdraw so that police could clear the site of " illegal organizations ".

The ultimatum came after Erdogan on Wednesday made his first concession yet by offering to hold a popular vote on plans to build a replica of Ottoman - era military barracks in the park.

Demonstrators, many still reeling from Tuesday ' s violence that sent clouds of acrid tear gas into their tents, have reacted coolly to the referendum idea and criticized the government for cherry - picking the representatives invited to the talks.

" We don ' t agree(with the referendum). We are angry that Tayyip spoke to people who don ' t represent us, " said 29 - year - old Iskender Sisman, sitting outside a tent in Gezi Park.

" Tayyip must apologize for everything, for the park, for the tear gas, " he added.

Erdogan, who has branded the protesters " extremists " and " looters ", has faced international condemnation over his handling of the crisis.

Four people have been killed and nearly 5,000 demonstrators during the unrest, tarnishing Turkey ' s image as a model of democracy in the region.