Tickets for the Manchester Derby at NRG stadium will not go on sale Tuesday, as planned, following the explosion at the concert in Manchester.

The event organizer, Relevant Sports, released the following statement:

"In light of the terrible tragedy in Manchester last night, we are postponing the on-sale of Manchester United v. Manchester City. Our thoughts and prayers are with the victims and their families."

Police suspect terrorism after an explosion that killed at least 19 and about 50 people at an Ariana Grande concert in Manchester, England.

RELATED: Police suspect terrorism after 19 killed, 50 hurt at Ariana Grande concert

Houston will play host to Manchester United F.C. and Manchester City F.C. at 8:30 p.m. July 20 at NRG Stadium.

RELATED: Houston to host Manchester City, Manchester United at NRG Stadium