Opposition parties in Nigeria have called for the presidential election to be scrapped, describing it as a sham.

The Peoples Democratic Party (PDP) and the Labour Party said results had been manipulated, leaving the poll irretrievably compromised.

Ruling party candidate Bola Tinubu is currently in the lead with just over 44% of the vote, official results released so far show.

The electoral commission has not yet commented on the opposition's demand.

"I demand that this sham of an election be cancelled and we call on Inec [the Independent National Electoral Commission] to conduct fresh elections within the window period provided by the electoral act," said Julius Abure, chairman of the Labour Party.

The African Democratic Congress (ADC) has also backed the call by Labour and the PDP, which is the main opposition party, for a fresh election to be held.