- The bank posted a net loss of 1.593 billion Swiss francs ($1.66 billion) on Wednesday.
- It also announced the immediate resignation of CEO Thomas Gottstein, who will be replaced by asset management CEO Ulrich Koerner.
- Asked if he had any plans to sell the company or merge with another bank, Lehmann said "that is a clear no."
The bank posted a net loss of 1.593 billion Swiss francs ($1.66 billion) on Wednesday and announced the immediate resignation of CEO Thomas Gottstein, who will be replaced by asset management CEO Ulrich Koerner.
Credit Suisse vowed to ramp up its efforts to overhaul the group's structure in the wake of mounting losses and a string of scandals — most notably the Archegos hedge fund collapse — that have resulted in substantial litigation costs.
Speculation has emerged in recent months that Credit Suisse may be considering a capital raise and even a possible sale of the company, but Lehmann told CNBC's Geoff Cutmore Wednesday that neither was in the cards.
"On capital, we reported, despite the loss today, a CET1 ratio of 13.5%. I am happy to see that number and we will guide the market also, in light of the uncertainty, that we are certainly going to defend our CET1 ratio until the end of the year, between 13 and 14%," Lehmann said. CET 1, or common equity tier one capital, ratio is a measure of a bank's solvency.
"So I think we are good on that one, and we will manage that very, very tightly."
He also branded some of the speculation — such as the suggestion in a Swiss blog early last month that U.S. bank State Street could be readying a takeover bid for Credit Suisse — as "quite ridiculous."
Asked if he had any plans to sell the company or merge with another bank, Lehmann said "that is a clear no."
Credit Suisse has launched a strategic review as it looks to cut costs, redirect its wealth and asset management operations and overhaul its compliance and risk management functions.
In Wednesday's earnings report, the bank said it will provide further details on the progress of the review in the third quarter.
"We will be even more focused going forward on our wealth management franchise, multi-specialist asset manager and the very, very strong Swiss business," Lehmann said.
"We will have a highly competitive banking business and we will align the markets business better to serve the needs of our wealth management and Swiss clients."
He added that the board wishes to bring down its absolute cost base to less than 15.5 billion Swiss francs in the medium term.
However, Lehmann refused to be drawn on how many job losses this will entail, instead promising more detailed plans for the cost-cutting strategy in the third-quarter earnings.