By Humeyra Pamuk
ISTANBUL (Reuters) - Turkish Prime Minister Tayyip Erdogan made one of his strongest calls yet for the country to "make a jump" towards a presidential system, saying Sunday's election will nurture people's enthusiasm for the kind of executive presidency he has long sought.
His vision for a strong, hands-on president sets him in sharp contrast with his main rival, Ekmeleddin Ihsanoglu, who has warned against an executive-style system, arguing that the head of state should be impartial and rise above the turbulence of daily politics.
The stark difference between the two main rivals' visions for the role of the president means the Sunday election is not only about choosing who should be Turkey's 12th President but also how that President should rule.
"I see that my nation will embrace the presidential system with this election and will start talking about it," Erdogan told Kanal 24 television late on Monday.
"They will say 'I chose the president, why should I not choose an executive president' ... It makes sense for advanced countries to generally have a presidential system, or a semi-presidential system," he said. "We have to make a jump."
Turks will vote directly for their president for the first time on Aug. 10. Previous heads of state have been chosen by parliament.
Erdogan, widely expected to win the vote, has long advocated reform of Turkey's parliamentary regime, making no secret of his ambition to become a stronger and a more active president than incumbent Abdullah Gul.
Ihsanoglu, a veteran Islamic scholar nominated jointly by opposition parties, has based his campaign on the opposite principle, warning that a president with a political agenda would only add to the strains within Turkish society.
"The president should be distant to all political parties and he should not dictate his own terms. There could be times of crisis, and I think the president has to be neutral to ease the tensions," Ihsanoglu told Reuters last month.
After dominating Turkish politics for over a decade, few doubt Erdogan will beat Ihsanoglu and the third candidate Selahattin Demirtas, a young Kurdish politician, with polls last month suggesting the premier could win in the first round.
Erdogan's opponents say his victory would only tighten his grip, concentrating more power in the hands of a man they say has polarized Turkish society along secular-religious lines and worried Turkey's Western allies.
Turkey's constitution makes reference to the necessity of the president being impartial, saying that the president-elect should cut any ties with his party.
But it also arms the president with powers such as chairing cabinet meetings, an article Erdogan frequently cites as the basis for his bid for a stronger presidency.
"I may not find my once a week meeting with the prime minister sufficient and we might introduce a different working basis here," Erdogan told Kanal 24. "Let's say the cabinet would meet once a week or once every fortnight, and you (as the president) would attend once a month."
Introducing an executive presidency would require changes to the constitution, which could be easier for the ruling AK Party if it wins a stronger parliamentary majority in elections next year. A two-thirds majority in parliament would be enough to enact constitutional changes without the need for a referendum.
Senior party officials have told Reuters that Erdogan is likely in the meantime to work with a 'council of wise men' to help him oversee top government business. They say the presidency's weight will be felt more in decisions.
Ihsanoglu warned that the last time a Turkish president got tangled up in the country's tumultuous politics, one of the country's worst economic crises quickly followed, referring to a fight at the top of the state in 2001 which ignited a collapse of the lira and a meltdown in the banking sector.
Markets plunged, the lira halved in value and the Turkish economy went into a long and painful crisis after former prime minister Bulent Ecevit said then-President Ahmet Necdet Sezer had thrown the constitution at him during a meeting.
"The place of the head of the state is not one for improvisation. He has to be calm, balanced and cool-headed," Ihsanoglu said.
(Editing by Daren Butler, Nick Tattersall and Hugh Lawson)