Brian Cowen has effectively denied "overruling" his minister for finance, Brian Lenihan, on the night of the guarantee.
The former Taoiseach says he and Mr Lenihan were "not being adversarial or confrontational" when they discussed their options in September 2008.
Mr Cowen has told the Banking Inquiry that Mr Lenihan wanted to nationalise Anglo, and only extend a bank guarantee to the other banks.
However, Mr Cowen said nationalising Anglo was too risky because it meant the State would permanently take over Anglo's liabilities, while a temporary bank guarantee carried lower risk.