El-Nasr refused to play against Arab Contractors in a league game on Wednesday "to show their solidarity with the Egyptian Army's martyrs."
17 Egyptian army officers and soldiers were killed and 13 wounded in clashes with IS-affiliated militants in North Sinai on Wednesday morning.
"I don't know how we can play in such circumstances," El-Nasr coach Sayed Eid told a TV program on Wednesday.
"We waited for a decision from the EFA to postpone Wednesday's games, but we were surprised by their ability to ignore the matter."
"There is no intention to withdraw from the league; we refused to play Arab Contactors only."
With two weeks remaining in the Egyptian League, El-Nasr, who made their first appearance in the Egyptian Premier League this season, are mathematically relegated to the second division as they lie 18 th in the league table with 32 points.
The Egyptian football association (EFA) said on Wednesdaty "there is no reason to postpone the Egyptian League."
The EFA said they will decide later sanctions against the relegated side.
Five league matches started on time today.
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