Johansson has resigned with immediate effect from today. He joined UBS in March last year after 22 years at Morgan Stanley, where his last position was vice-chairman for Europe.
Replacing Johansson, UBS has named Alex Wilmot-Sitwell and Carsten Kengeter as co-chief executives of the investment bank. Wilmot-Sitwell has been at the bank since 1996 and has been chairman and chief executive of the UBS group in Europe, the Middle East & Africa (EMEA) since January 2008; before that, he was joint global head of the investment banking department from November 2005.
Kengeter was most recently the joint global head of fixed income, currencies and commodities within UBS's investment banking division.
Oswald Grübel, group chief executive of UBS, commented: "Under their joint leadership we will continue to build on the strong core businesses of our investment bank and remediate our legacy risks. Our investment bank is indispensable to our global firm and to our integrated business model."
These latest management changes follow replacements of several other senior executives at the bank recently. In February, Grübel, previously group chief executive of Credit Suisse, took over from Marcel Rohner as chief executive.
At UBS's annual general meeting on April 15, the bank elected its next chairman, Kaspar Villiger. This was a widely expected move, since previous chairman Peter Kurer announced on March 4 that he would not stand for re-election. Villiger is a former finance minister for the Swiss government and most recently sat on the boards of three Swiss corporations: reinsurer Swiss Re, food manufacturer Nestlé and newspaper Neue Zürcher Zeitung.
Also at the annual general meeting, Grübel predicted the bank would make a Sfr2 billion loss for the first quarter of 2009. In addition, he revealed planned cost-cutting measures, including shedding 8,300 of its 76,200 employees by the end of 2010.