Labor has accused the State Government of playing politics with the sport of mixed martial arts and endangering the safety of competitors.
MMA is a combat sport that involves striking and grappling techniques from disciplines such as boxing, kickboxing, wrestling and Brazilian jiu-jitsu.
The bouts are held in a cage.
Sports Minister Terry Waldron said this month the cages were "not in the community's best interests" and would be illegal from early March.
The decision went against the advice of the Combat Sports Commission and was attacked by key figures in Perth's MMA community, as well as the sport's biggest promoter, the US-based Ultimate Fighting Championship.
Tom Wright, UFC director of operations for Australia, New Zealand and Canada, said the ban had jeopardised plans to hold an event at Perth Arena.
"We know there's a great new venue there, the Perth Arena, it's the perfect size for our sport," he said.
"We were most definitely thinking about bringing an event to Perth as early as the end of this year or 2014."
Mr Wright described the ban as ill-advised and said a fenced-in ring was the safest option.
Shadow sports minister Mick Murray said the Government needed to focus on safety and had to avoid driving the sport underground.
Mr Murray, who said there were aspects of the sport he did not like, said he would revisit the ban if Labor won the March 9 State election.
"Images and perceptions are one thing, reality is another," he said.
"What happens if a fighter or a pair of them fall out of the ring and injure themselves?
"The Government has had plenty of time and they've done this right before an election.
"Don't play politics with it - look after the safety and welfare of the fighters."
Mr Waldron said last week there were other ways to protect the fighters, including mats outside the ring and extra ropes.
"I just don't think the cage sends a good message and I don't think the majority of people in WA accept the cage either," he said.