US private equity firm TPG is confident of securing finance for two of its largest potential buyouts this year despite rivals delaying deals due to fluctuations in the debt markets.

According to sources close to the process, TPG has already arranged banks to put together the debt component backing its potential offer for Spanish airline Iberia. The firm made informal approaches to banks when it made its €3.4bn ($4.7bn) indicative bid earlier in the year. A source said although mandates with the banks are not "signed and sealed", confidential agreements have been sent to the financial institutions backing the deal.