Gul served in the largely ceremonial post of president from 2007 to 2014, while his close ally, Erdogan, was prime minister, and before that as a widely respected foreign minister.
But since Erdogan took over as president and steered Turkey towards a system in which the head of state has wide-ranging executive powers, Gul has largely stepped back from frontline politics, though analysts say he has been unhappy with the country’s political direction. Some have even pointed to Gul as a leader who could unite Erdogan’s disparate opponents.
"I said the parliamentary system is more accurate for Turkey even while I was the president. My choice is for a fully democratic parliamentary system. Parliament has never been this insignificant until today. Turkey feels the absence of it," Gul said in an interview with Karar newspaperpublished on Tuesday.
Turkey voted to move to the new system in a referendum in 2017, held during a period of emergency rule following a failed coup attempt in July 2016. The new system did away with the position of prime minister and allowed Erdogan to pass laws by decree and tied key institutions, as well as much financial control, to the presidency.
Erdogan’s Justice and Development Party (AKP) maintains the new system allows for the smoother running of government, but critics say it has emasculated parliament and ushered in one-man rule.
Gul also voiced concern over Turkey’s policy in Syria, where 13 Turkish soldiers were killed in shelling by Russian-backed Syrian government forces this month.
“What I will say, that even if we are very provoked, is not to enter an all-out war with Syria,” Gul said.
Turkey has been involved in the crisis in Syria since the war broke out in 2011 without a proper exit plan, and had enhanced collaboration with Russia while drifting away from its Western allies, he said.
Turkey’s problems with the United States have also drawn it closer to Moscow, but drifting away from the West would weaken Turkish democracy, Gul said.
"Turkey needs to be part of the Western bloc together with Europe to ensure a democratic and pluralistic country. In this respect, its recent relations with Russia are off-balance," he said.
Gul said Turkey's Kurdish question had become a regional and international issue after the 2015 collapse of a promising ceasefire between the government and the Kurdistan Workers’ Party (PKK), and the subsequent Turkish invasion of Kurdish-held northern parts of Syria.
"It is all our responsibility. When we could not solve it within our initiative through high human rights standards, it gained regional and international dimensions, these are tough jobs," he said.
Gul also criticised the government's purchase of Russian S-400 air defence missiles, despite the objections of Turkey’s NATO allies.
The United States opposes the S-400 deal since the Russian system is not compatible with NATO systems and due to fears that Turkey’s deployment of the missiles would allow Russia to glean sensitive information about the defences of NATO’s advanced fighter jets.
The former president said Turkey's S-400 acquisition could undermine the power of its army, the second largest in NATO after that of the United States.
"Because ultimately all the standards of the Turkish Armed Forces (TSK), everything from its air force to ground forces is at NATO standards. The strength of the TSK comes from that," Gul said.
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