The 12-time champions have once again questioned the integrity of the refereeing in their league and insist they are "not joking this time" about leaving

Zamalek have threatened to quit the Egyptian Premier League once again due to what they claim to be unfair refereeing.

It is not the first time the 12-time national champions have announced their intention to leave the country's top flight, with their most recent announcement coming back in May in similar circumstances.

On this occasion, Zamalek are unhappy with a penalty awarded to rivals Al Ahly in their match against Misr El-Maqassa on Sunday, which was scored to secure a 1-0 victory.

The result saw Al Ahly maintain their position at the top of the Egyptian league, with Zamalek trailing 14 points behind in seventh partially as a result of the fact they have played four games fewer.

And yet again Zamalek have questioned the integrity of the officiating, insisting they will forfeit their place in the division unless the game's referee, Ibrahim Nour El-Dein, is removed from his position.

"We will not continue this Egyptian Premier League season," club president Mortada Mansour said, according to KingFut.com. "Ibrahim Nour El-Dein is corrupt and I will not let him get away with it.

"[Egyptian Football Association president] Hany Abou Rida is not free to follow the league standards. I will not continue this Premier League season; officials are ruining it.

"I'm not joking this time, the whole board is against continuing this season. It's either we don't play the next match or I leave. I will not accept pressure from officials.

"When we have an FA that respects clubs and officials on a better level only then will we continue the league."

The club's Twitter account appeared to mock the Al Ahly result by posting an image of sarcastic applause after the full-time whistle on Sunday.

In October, Mansour and Zamalek drew criticism for making the racially charged claim that "black magic" cost them victory in the African Champions League final against South African side Mamelodi Sundowns.