Losing presidential candidate Prabowo Subianto and his campaign team will challenge the election results at the Constitutional Court following the official announcement of the victory of incumbent President Joko “Jokowi” Widodo.

The General Elections Commission (KPU) announced the final vote count and named the Jokowi- and Ma’ruf Amin ticket the winner of the presidential election with 85.6 million votes, 55.5 percent of the vote. The Gerindra Party chairman and his running mate Sandiaga Uno gained 68.7 million votes, 44.5 percent.

“We reject the final presidential vote tally by the KPU. And we’ll take all available legal avenues supported by the Constitution,” Prabowo said on Tuesday at his home in South Jakarta.

Read also: Jokowi declares reelection victory at 'kampung deret'

Gerindra deputy chairman Sufmi Dasco Ahmad said Prabowo would file a lawsuit after previously saying he would not take the matter to the courts.

“We’ve already had a meeting and decided to file a lawsuit. Now we’re preparing all materials,” Sufmi said.

Prabowo said the KPU’s vote tally contained irregularities.

“In addition, the announcement was not in line with the schedule,” Prabowo said, referring to the fact that the poll body announced the results in the early hours of Tuesday, earlier than its planned announcement on May 22.

Read also: Security at highest level following KPU vote tally announcement

KPU head Arief Budiman said the losing candidate pair had until Friday to file a lawsuit to contest the results, within three days of the official announcement of the vote tally.

If no legal challenge is filed, the KPU will officially name Jokowi and Ma’ruf the president- and vice president-elect for the 2019-2024 period on Friday, Arief said.

Prabowo’s camp has accused the government of committing massive and systematic fraud since election day on April 17.

The Elections Supervisory Agency (Bawaslu) rejected on Monday a report filed by Prabowo’s campaign team that accused Jokowi’s camp of committing “structured, systematic and massive” campaign violations.