State-owned power company Vattenfall bought the Dutch firm Nuon in 2009. It was subsequently downgraded in value to the tune of SEK 60 billion.
Reinfeldt told the committee he only found out about the deal after the fact, backing up Finance Minister Anders Borg, who told the committee that he only found out by reading articles in the Swedish press.
That differs from notes on a memo written at the time at the industry ministry, which claims then-Industry Minister Maud Olofsson had informed the prime minister of the deal.
Olofsson, who was also the leader of the Centre Party, has left politics and refuses to come before the parliamentary committee to explain her actions at the time.
The constitutional committee is trying to get to the bottom of how the Nuon deal could have been agreed. It is the costliest deal in Swedish history, despite warning signals that the Dutch company may have been over-priced.