Suncorp will work toward a AA credit rating over the long term, the bank's managing director, John Mulcahy, told the Financial Review. He said a AA credit rating was achievable.That long-term aim may turn out to apply only to Suncorp's insurance business.In a separate interview with The Age, Mulcahy said it would be emotionally difficult to give up bank and wealth business, but says the right decision would be made if it provided better value for shareholders.Suncorp turned down an offer from ANZ to buy the business two weeks ago. ANZ's was the only bid."I think it's a highly regarded asset and others will show interest," he told the newspaper. "We're not soliciting it - we just need to run it well. If people come and make an appropriate offer we will consider it.""We wouldn't have accepted the offer in any circumstances - it was an insufficient offer," he said.