gordian knot

The peace talks have become a gordian knot that no one can untangle.

How do we cut this gordian knot and finally move forward?

The budget dispute became a gordian knot for the entire team.

Sometimes you just have to cut the gordian knot instead of trying to untie it.

The gordian knot of healthcare reform has stumped politicians for decades.

She refused to see it as a gordian knot — she believed there was always a clear solution.