The congress will adopt a new programme designed to tackle purported remnants of totalitarianism and secure the nation's survival.

Around 800 delegates and more than 250 domestic and foreign guests have been announced at the event, to be organised at the Catholic education centre Zavod Antona Martina Slomška in Maribor.

The office of the Hungarian prime minister has confirmed for the Večer newspaper that Orban will be among those addressing the congress at Janša's invitation.

The SDS, which will also appoint its executive and supervisory committees, has not disclosed any candidate names, it is however expected that Janša, who last had a rival candidate in 1993, will run for president again.

Janša's control on the party, which won the 2004 election and came to power again for two years in 2012 as the runner-up, has been growing steadily and the SDS has also been firmly in the lead in opinion polls the better part of a year.

A reappointment thus seems almost certain, even though cracks appeared in the SDS in 2014. That year, the party secured only 21 MPs, 15 fewer than the newly formed centre-left Miro Cerar Party (SMC), in an election marked by Janša's several months-long prison stay.

Janša was jailed over bribery in a defence contract with Patria and while he was released on procedural grounds, he has recently again made headlines as financial investigators accused him of having almost EUR 400,000 in unaccounted for assets. In late 2012, the SDS-led government collapsed over corruption allegations against Janša.

Certain senior members as well as two MPs recently left the party, while 2016 also brought a rift with the SDS's traditional centre-right ally, the New Slovenia (NSi).

NSi leader Ljudmila Novak has de facto accused Janša of embracing totalitarian strategies when handling power relations on the right, but the emergence of new parties widely seen as close to Janša gives SDS supporters hope the party could get another shot at running the government after the 2018 general election.

The congress is meanwhile to confirm the SDS's Slovenia at Heart election platform, whose draft lists key issues and challenges for Slovenia.

According to the party, Slovenia and the EU are faced with huge challenges and uncertain future. Slovenia's situation ahead of this uncertain future is worrying.

The transition from the totalitarian regime to a modern open society has failed in many areas. "Instead of a relaxed and confident society proud of itself and open to the world, we have a stuffy bureaucratic atmosphere in which the government and behind-the-scene networks want to control everything."

The document also says that Slovenia is faced "with abuse from state institutions, snatched elections and subsequently amateur government". What is more, the incumbent government is "passive in tackling common problems and lacks a vision in case of further disintegration processes within the EU".

The SDS therefore proposes a set of measures to respond to the European crisis and the uncertain future.

It calls for strengthening national unity and fresh ideas for maintaining European integration as well as finding strategic ways that would secure Slovenia's existence and future even in the event of continued disintegration of the EU.

The family would be the focal point of the society. "The family will become an investment project and not a part of social policies. Only bigger families can preserve Slovenian culture and nation for tomorrow."

The party would thus enable affordable housing loans for young families with the principal going down 20% for every newborn.

The SDS also took a swing at the amount of funds the government earmarks for migrants and asylum seekers, arguing that national homogeneity is Slovenia's huge advantage, one which benefits it in uncertain times.

To provide security, which is a fundamental right, the SDS would increase defence spending and the number of active and reserve troops.

The party would also strive for equal opportunities for all Slovenians, for cutting red tape, modernising education, and sorting out the healthcare system.