Citigroup chief executive Vikram Pandit said the banking giant was profitable in the first two months of 2009, generating total revenue in that time of $19 billion, excluding externally disclosed marks.

It was the firm’s best quarter-to-date performance since the third quarter of 2007, Pandit said in a memo sent out late last night to all Citigroup employees.

“In addition to our strong capital position, I am most encouraged with the strength of our business so far in 2009,” Pandit said.

Pandit emphasized that the bank’s tangible common equity could increase to as much as $81 billion assuming 100 percent participation in a preferred exchange announced almost two weeks ago. The move could give the U.S. government a 36 percent stake in the bank.

The government aid “is expected to make Citi the strongest capitalized large U.S. bank” in terms of TCE, he said.