“[The congress] will formulate an action plan and set out major policy direction that will meet the demands of the era,” the party’s decision-making Politburo said in a statement after its meeting on Thursday, according to state media reports.

The congress date is expected to be ratified by the party’s 200-strong Central Committee when it meets at its seventh and the last plenum on October 11.

Analysts have said Xi is likely to lend his name to the philosophy, which would put him on a par with Mao Zedong and Deng Xiaoping.

The heavily scripted Politburo statement said the congress will “implement the spirit of General Secretary Xi Jinping’s series of important speeches, and the Party Central’s new concepts, new thinking and new strategies on the governance of the country”.

The wording was a departure from previous official statements that omitted “the Party Central” and promised to “comprehensively” or “thoroughly” implement Xi’s direction.

Chen Daoyin, a political scientist at the Shanghai University of Political Science and Law, said the departure could signal resistance within the party against Xi’s attempts to build absolute authority.

“State media a month ago was drumming up Xi’s personal authority, using terms like ‘Xi Jinping thought’ and ‘the great leader’,” Chen said. “We could see signs of compromise and internal resistance against his efforts to achieve absolute personal authority.”

In the past, the seventh plenum – usually convened only days before the next party congress meeting – has passed a new list of vice-chairmen of the powerful Central Military Commission. It has also officially confirmed the date of the next party congress meeting, proposed by the Politburo.

Official records also show that the plenum could also ratify the expulsion of corrupt officials from the party if they were members of the Central Committee and netted in the past 12 months.

Sun Zhengcai, former party chief of Chongqing, was sacked in July, accused of “serious violation of discipline” – a term that usually refers to corruption or political disloyalty.

Chen said the programme for this year’s congress had mostly been determined after Xi addressed the country’s top officials in a final preparatory meeting in Beijing in July.

He added that the party was expected to reach consensus on the personnel reshuffle at the plenum, as well as Xi’s political report.

Ahead of the congress, the party has embarked on a propaganda campaign promoting the president, including airing a documentary series lauding Xi’s achievements and publishing a book on his experiences as a youth.

“The party is busy creating a positive public image for Xi,” Chen said. “It would be really embarrassing if anything failed to be passed at the meeting.”

Chen said the October date also gave bureaucrats enough time to turn Xi’s directions into concrete policies to be approved at the annual parliamentary meeting early next year.

“The police and military will need to put security measures in place,” said Beijing-based historian Zhang Lifan. “And the propaganda organs need to mobilise public opinion.”

The documents to be unveiled at the congress, including Xi’s key political report, would also be finalised in the coming months, Zhang said.

Kerry Brown, a professor of Chinese politics at King’s College London, said a regular date for the congress added predictability to China’s political system.

“They are trying to create a sense that the Communist Party is institutionalising itself,” Brown said. “It’s unlikely that everything has been decided now. A bit more time might be necessary.”

Brown said organisers would have also sought to avoid clashes with other political events, such as visits by state leaders and the National Day celebrations.

“They don’t want any distractions,” he said. “On the whole, mid or late October is usually a quiet time for them to do this.”

The dates of the congresses in 1997, 2002 and 2007 were all announced in late August of those years, with the gatherings themselves held between mid-September and early November.

A one-month delay in announcing the 18th party congress date five years ago led to speculation that power struggles among the party’s elite had prevented them from finalising the leadership candidates.

The speculation was further fuelled when then president-in-waiting Xi went missing for nearly two weeks, skipping scheduled meetings with visiting foreign dignitaries including then US Secretary of State Hillary Rodham Clinton, Singaporean Prime Minister Lee Hsien Loong and former Danish Prime Minister Helle Thorning-Schmidt.

About 2,300 congress delegates will vote on a new Central Committee, which will then endorse leadership appointments and constitutional changes.

Observers will be watching closely to see if Xi can have his associates elevated to important positions.

He will also deliver a political report, in which he will sum up his achievements and give directions on the country’s future political, social and economic policies.

Additional reporting by Nectar Gan and Choi Chi-yuk

Previous Communist Party National Congress announcements

18th National Congress – opened November 8, 2012; announced September 28

17th National Congress – opened October 15, 2007; announced August 28

16th National Congress – opened November 8, 2002; announced August 25

15th National Congress – opened September 12, 1997; announced August 27