Xi urges stand against 'grim' challenges

Hailing the start of a "new era", President Xi Jinping has outlined a vision in which China would become a "great modern socialist country" by mid-century.

President Xi Jinping has urged a reinvigorated Communist Party to take stronger role in society. (AAP)

Chinese President Xi Jinping has urged a reinvigorated Communist Party to take a stronger role in society and economic development to better address the nation's "grim" challenges as he opened a twice-a-decade national congress.

Speaking in the massive Great Hall of the People near Tiananmen Square, Xi laid out his vision of a ruling party that serves as the vanguard for everything from defending national security to providing moral guidance to ordinary Chinese.

He struck a nationalistic line throughout his speech, calling for the party not only to safeguard China's sovereignty but also to revitalise Chinese culture, oppose "erroneous" ideology and promote religion that is "Chinese in orientation".

"The great rejuvenation of the Chinese nation is no walk in the park or mere drum-beating and gong-clanging. The whole party must be prepared to make ever more difficult and harder efforts," Xi told hundreds of delegates, mostly men in dark suits who applauded regularly as they read copies of his prepared remarks.

"To achieve great dreams there must be a great struggle."

Hailing the start of a "new era", Xi outlined a vision in which the party would lead China on the road to becoming a "great modern socialist country" by mid-century.

Xi wields undisputed power and is expected to get a second five-year term as party leader at the gathering. Analysts say he has consolidated his power by sidelining his competitors in other intra-party cliques, including those surrounding his immediate predecessor Hu Jintao and former leader Jiang Zemin.

Xi, in his three-and-a-half-hour address, said China's "prospects are bright but the challenges are grim", a rare acknowledgement of severe economic issues.

He added that the party would have to take big risks and overcome "major resistance".

Among the grave issues Xi said were insufficiently addressed are a widening income gap and problems in employment, education, medical care and other areas.

He pledged to make high school universally available and promised to extend land-use contracts for farmers for another 30 years after expiration.