ISTANBUL (AFP) - Turkish protesters refused to back down on Monday after Prime Minister Recep Tayyip Erdogan warned they would "pay a price" for their unrelenting demonstrations against his Islamic-rooted government's decade-long rule.

As riot police doused of thousands of protesters in the capital Ankara with tear gas and jets of water for a second straight night, Mr Erdogan fired up supporters of his ruling Justice and Development Party (AKP) with combative rhetoric in rallies across the country.

"Those who do not respect this nation's party in power will pay a price," he told thousands of cheering loyalists in Ankara, just a few kilometres from the clashes in downtown Kizilay Square, the latest violence in a second week of mass civil unrest.

"We remained patient, we are still patient but there's a limit to our patience," Mr Erdogan said.

His fans relished the show of strength, frequently interrupting his remarks with bursts of applause and chanting: "Turkey is proud of you."

Tens of thousands of anti-government demonstrators stepped up their protests over the weekend, pouring into cities across the country including Istanbul, Ankara and the western city of Izmir.

Istanbul's Taksim Square, the symbolic heart of the protest movement, attracted some of the largest crowds yet, with people dancing and chanting "Erdogan, resign!" into the early hours in a festive atmosphere.

The unrest first erupted on May 31 with a tough police crackdown on a campaign to save Istanbul's Gezi Park, which borders Taksim Square, from demolition. The trouble spiralled into nationwide displays of anger against Mr Erdogan and his party, seen as increasingly authoritarian.

Nearly 5,000 demonstrators, scores of whom are young and middle-class, have been injured and three people have died in the trouble, tarnishing Turkey's image as a model of Islamic democracy.

Taksim, which has seen no police presence for over a week, was much quieter on Monday as demonstrators resumed their normal routines, though many vowed they would return.

"We are going to school now, but we will come back later," said 17-year-old Etem Yakin as she crossed the square, where a clean-up operation was in full swing.

She said the premier was pouring oil on the flames with his confrontational stance. "If he keeps talking like this, we will keep up like this too."

Mr Erdogan was to meet government ministers in Ankara later on Monday, with the crisis expected to top the agenda.

"I honestly don't know where this is going," said Mr Akif Burak Atlar, secretary of Taksim Solidarity, a group representing the original Gezi Park campaigners.

"It was his speeches and the police brutality that led the protests this far in the first place. He needs to take a step back."

Opponents accuse Mr Erdogan, in power since 2002, of repressing critics - including journalists, minority Kurds and the military - and of pushing conservative Islamic values on the mainly Muslim but staunchly secular nation.

But the 59-year-old is also considered the most influential leader since Mustafa Kemal Ataturk, the father of modern Turkey, and remains the country's most popular politician.

His AKP has won three elections in a row and took nearly half the vote in the 2011 elections, having presided over strong economic growth.

On his whistlestop tour of three cities on Sunday, the premier urged loyalists to respond to the demonstrators by voting for the AKP in local polls next year.

"I want you to teach them a first lesson through democratic means at the ballot box," he said.

Turkey will see both local and presidential elections in 2014.

The AKP plans to launch its first campaign rallies in Ankara and Istanbul next weekend, expected to bring tens of thousands into the streets.

A general election is scheduled for 2015, and officials have ruled out any suggestion of calling early polls in view of the crisis.

The national doctors' union says the unrest has left two protesters and a policeman dead so far while almost 4,800 people have been injured.

Mr Erdogan said on Sunday that over 600 police officers have been hurt.

He again dismissed the demonstrators as "looters" and "extremists", but Mr Hugh Pope of the International Crisis Group said Mr Erdogan should "engage the mainstream protesters to make it easier to reach a peaceful resolution".

"There's no need for drastic measures," he added.

Mr Erdogan has faced international condemnation for his handling of the unrest in Turkey, a country of 76 million at the crossroads of East and West and a key strategic partner in the region for the United States and other Western allies.