Upcoming anti-government rallies on 30 June, which will likely affect national football activity, prompted Zamalek's Portuguese coach Jorvan Vieira to leave the country on Friday for an open-ended holiday, the club has announced.

Egypt's 'Rebel' campaign – a signature drive launched in May calling for a "withdrawal of confidence" from President Mohamed Morsi – has called for mass protests on Sunday to demand Morsi's ouster and snap presidential polls.

"Vieira informed the team's technical staff that he would leave Egypt on Friday," an official Zamalek club source told DPA on Thursday.

"He said he would return to Egypt when the country re-establishes a degree of calm," the source added.

Vieira's fate with Zamalek remains uncertain, as his contract with the club is set to expire at the end of June. Until now, he has declined offers to renew his contract.

Earlier this week, the Egyptian Premier League was postponed "indefinitely" due to ongoing "security concerns."

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