An air carrier First Officer reported the Captain took evasive action to avoid colliding with a foreign air carrier's A330 which entered DTW Taxiway H without clearance.

Narrative

On taxi out to Runway 22L in DTW; as we were northbound on Taxiway Y just passing Victor; and were cleared to taxi on Y to 22L; off our right wing an Airbus A330 came at about 30 or 40 KTS on Taxiway H. At the time I was briefing the Captain for the takeoff and was heads down. We had numerous deferrals including a deferred FMS. She then said; 'Is he going to stop?' and as she said that; I looked up to see this massive plane coming on an intercept and she stopped the aircraft. At that point she asked Ground 'Hey is that plane off our right going to stop?' The Airbus made a hard right turn; and it appeared that its left wing came into close proximity to our tail. Ground then asked the aircraft who he was; and we heard no reply from him because he was on a different frequency. The Ground Controller then responded; 'Aircraft on Taxiway H; Taxiway Hotel is an active taxiway and you need clearance to taxi on it.' We didn't hear the Airbus's response; and recalled learning that this Ground Controller was controlling the entire airport. The Airbus ended up facing north on Taxiway K. We stopped the aircraft right before K11. We had numerous threats; including a deferred FMS; bad weather and a deferred automatic fuel transfer system. I should have kept my eyes peeled for some rouge foreign aircraft not taxing with a clearance at high speeds. Next time I will make it a point to never let myself get too heads down when briefing the Captain.