Similar to the B777, but no specific N1 percentage specified:

Takeoff Procedure
Do the normal Takeoff Procedure with the following modification:

When engine anti-ice is required and the OAT is 3°C or below, the takeoff
must be preceded by a static engine run-up. Use the following procedure:

Run-up to as high a thrust setting as practical and confirm stable
engine operation before the start of the takeoff roll.