so be it

Let it be so, I accept it as it is. For example, If you can't change the reservation, so be it; I'll travel on Monday. This phrase, often given as a translation of the Hebrew (and Greek and Latin) amen, has been employed in the current sense since about 1600.

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.