AIB Bank, the State's largest bank, has confirmed that it submitted an indicative bid to purchase Ulster Bank Group. In a statement to the Irish Stock Exchange, the bank confirmed its interest in the light of recent media reports but said it would be making no further comment at this stage. Ulster Bank's owner, National Westminster Bank, is selling or floating the bank as part of its defence against a hostile bid by Bank of Scotland. NatWest is also fighting a hostile bid by Royal Bank of Scotland.