(Reuters) - Spain's Unicaja and Liberbank confirmed on Wednesday they had held talks about a potential deal, driving shares in both banks higher on expectations of a tie-up.Spanish newspaper Expansion earlier reported that the banks were considering a merger to create Spain's sixth-largest lender by assets, with almost 96 billion euros (86.91 billion pounds).The banks confirmed in separate statements to the Spanish market regulator that they had been in contact as part of their regular..