Kenya’s opposition leader Raila Odinga has said his political alliance will be transformed into a “resistance movement”, as he called on supporters to boycott a presidential election rerun scheduled for Thursday.

Odinga made the remarks on Wednesday during a speech at Nairobi’s Uhuru Park, just hours after the country’s electoral commission said the vote would go ahead.

“Do not participate in any way in the sham election. Convince your friends, neighbours and everyone else to not participate,” he told supporters in the Kenyan capital.

“We advice Kenyans who value democracy and justice to hold vigilance prayers or stay at home,” added Odinga, leader of the National Super Alliance (NASA) coalition.

Reiterating that he will not take part in the poll, Odinga said his opposition alliance would now be transformed into a resistance movement against the government.

‘Getting messier’

Kenya is holding the election re-run after the country’s Supreme Court annulled the results of an August 8 poll, following a challenge by Odinga, due to “irregularities” and “illegalities” in the electoral process.

President Uhuru Kenyatta had been declared the winner of that vote.

Odinga pulled out of the new race earlier this month after claiming opposition demands to overhaul the country’s election body had not been met.

Earlier on Wednesday, a last-minute attempt to block the vote failed at the Supreme Court, which was unable to raise a quorum of judges to decide on whether the poll should go ahead.

“It’s getting messier, and we are going deep into crisis every other day,” Al Jazeera’s Mohammed Adow, reporting from Nairobi said.

“The opposition had pinned all their hopes on that court case but because of the quorum crisis at the Supreme Court – something that NASA is describing to be a result of government intimidation of independent institutions – we are now back to square one,” he added.

The petition to the Supreme Court was brought by three human rights activists who claimed the electoral commission is not ready to hold a credible poll.

“Regrettably and with due apology to all the parties, this matter cannot proceed to hearing this morning as earlier scheduled,” David Maraga, Kenya’s chief justice, told the court.

“It is accordingly adjourned to a date to be taken in the registry,” Maraga added.

Four of the bench’s seven judges were not present, Maraga said. Five judges are needed for a quorum.

Supporters greet Kenya’s President Uhuru Kenyatta during a rally in Nairobi on Monday [Simon Maina/AFP/Getty Images]

A lawyer for the opposition said the shortage of judges was not coincidental.

“The lack of quorum on the part of the Supreme Court is not by coincidence [or] by accident,” James Orengo told reporters outside the court.

“There is an attempt to undermine the authority of the institutions of government including independent institutions like the electoral commission and the Supreme Court,” Orengo said.

“If the commission dares goes on with the purported election tomorrow … it will be illegal and unconstitutional,” he added.

But William Ruto, Kenya’s deputy president, hit back, saying “the evil schemes to deny Kenyans the right to vote [have failed].

“We will decide and move our country forward tomorrow.”

Al Jazeera’s Hamza Mohamed contributed to this report from Nairobi.