From left, Frank Habineza, Paul Kagame and Philippe Mpayimana are running for president [AFP]

Rwandan President Paul Kagame is widely expected to secure a landslide victory over two little-known challengers and extend his 24-year rule as nine million voters head to the polls on Monday.

Kagame, who was first elected in 2,000, will face Frank Habineza, the leader of opposition Democratic Green Party, and former journalist, Philippe Mpayimana, running as an independent candidate.

The country will hold presidential and legislative elections on the same day with 589 candidates vying for the 80 seats in the lower house of parliament.

Key opposition figures like Victoire Ingabire and Bernard Ntaganda are barred from running due to past legal convictions – despite their appeals to have the sentences quashed.

Kagame could potentially stay in power until 2034 after a 2015 constitutional amendment reset the clock for him by changing presidential terms from seven to five years.

Kagame has won more than 90% of the vote in the three previous elections, and his regime is credited with rebuilding a traumatized nation after the genocide in 1994, according to AFP.

But his regime is widely criticized by rights groups as autocratic, stifling the media and political opposition with arbitrary detentions.

Kagame faces criticisms for allegedly fueling decades of conflict in the neighbouring Democratic Republic of Congo, where a UN report says Rwandan troops are fighting alongside M23 rebels in the troubled east.