The PUK said its decision to ignore the results, which have yet to be announced, was based on what it described as fraud in the voting process.
The PUK is competing with its long-time rival the Kurdistan Democratic Party (KDP) in the election as discontent grows with perceived corruption and economic hardship, Reuters reported.
Splits within the PUK could give the KDP an upper hand in their power-sharing arrangement, which has been fraught with tensions.
While criticism of the ruling Kurdish establishment has grown more vocal, a weak opposition means many voters may stick to traditional leaders.
“I don’t know who I will vote for, but our family has always supported the KDP. My son will pick a candidate for me,” said Halima Ahmed, 65, as she walked with a cane in the city of Erbil, the seat of the Kurdistan Regional Government (KRG).
Preliminary results are expected within 72 hours. There are 111 seats being contested in the election, including 11 reserved for ethnic minorities.
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