Annular barrier and downhole system

An annular barrier to be expanded in an annulus between a well tubular metal structure and an inside wall of a borehole downhole to an expanded condition of the annular barrier providing zone isolation between a first zone and a second zone of the borehole, the annular barrier having an unexpanded condition, and the expanded condition comprising:

• a tubular metal part for mounting as part of the well tubular metal structure,
• an expandable metal sleeve surrounding the tubular metal part, each end of the expandable metal sleeve being connected with the tubular metal part defining an expandable space, the expandable metal sleeve having a first thickness,
• an expansion opening in the tubular metal part through which fluid enters in order to expand the expandable metal sleeve, and
• a valve assembly having a first opening fluidly connected with the first zone in the expanded condition of the annular barrier, a second opening fluidly connected with the second zone through a fluid channel between the tubular metal part and the expandable metal sleeve, and a third opening fluidly connected with the expandable space,
• wherein the fluid channel has an extension along a circumference of the tubular metal part being at least 5% of the circumference of the tubular metal part.