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  10 August 2015 Last updated at 01:41 BST
  New Zealand was one of the original nations involved in the TPP, which if a deal is concluded will  create a "mega regional" bloc with a combined GDP of $28 trillion.
  Mr Key explains why he was optimistic that an agreement will be reached.
  Go to the Asia Business Report website for more programme clips.
target: Talks between 12 nations to agree the Trans Pacific Partnership trade deal may have failed last week, but New Zealand's Prime Minister John Key has told the BBC that he is confident the pact will be signed by the end of the year.