LONDON (Reuters) - Premier Oil is mulling a $500 million (314m pound) bid for BPs gas production business in Pakistan, the Times said on Tuesday. Citing people familiar with the talks, the newspaper said it is not certain whether Premier or Mubadala, the Abu Dhabi sovereign wealth fund that has also expressed an interest in the assets, will participate in the bidding next month. BPs upstream assets in Pakistan comprise a number of producing fields and exploration blocks in the southern Sindh. The fields are worth $690m, UBS analysts estimated in a research note in July. Premier, which already has assets in southern Pakistan, was not immediately reachable for comment.