Manchester United's UEFA Super Cup clash with Real Madrid will include water breaks if soaring temperatures in Macedonia continue, sources have told ESPN FC.

United face Madrid in Skopje on Tuesday with the game set to be played in the midst of a heatwave that has led to health warnings having been issued in some European countries.

Temperatures in the Balkans have been as high 40 degrees Celsius in the build-up to the game, which will see Champions League winners Madrid and Europa League holders United face off.

If the temperature exceeds 32 degrees Celsius at kick-off at the Philip II Arena, UEFA will sanction water breaks on 30 and 60 minutes.

Real Madrid are the holders of the UEFA Super Cup. Michael Steele/Getty Images

However, with the game set to kick off at 8:45 p.m. local time, European football's governing body is hopeful the temperature will have dropped enough so that the additional breaks will not be needed.

United and Madrid should be used to the heat after both chose California for their preseason training base, with both sets of players facing stifling temperatures during training camps at UCLA in July.

United and Madrid have already played once this summer in Santa Clara, with United winning on penalties after a 1-1 draw at Levi's Stadium.

Madrid have announced Cristiano Ronaldo is part of their squad to play United despite only returning to training on Sunday.