Apax, the UK private equity firm, is keeping a close eye on the auction of Iberia, after the board of the Spanish airline last week allowed a consortium led by buyout rival TPG Capital conditional access to its books.

TPG Capital, which is part of a consortium with British Airways, will decide today whether to go ahead with due diligence after Iberia's board last Thursday granted it access to its finances, according to sources close to the situation. Access is conditional upon TPG making a binding offer closer to €4 per share.