Owen Williams gave the Scarlets an early lead, but tries from Tommy Bowe and Robbie Diack combined with Ruan Pienaar's reliable boot have left Ulster 18-3 up at half time.
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Wayne Pivac praised Scarlets' attacking style as they secured the Guinness PRO12 title with a stunning 46-22 success against Munster.
Scarlets sealed a famous victory at the Aviva Stadium in Dublin with an emphatic 46-22 victory over Munster in the Guiness PRO12 final.
Welsh holiday makers have been caught up in travel chaos after British Airlines cancel all flights from Heathrow and Gatwick.