UBS AG has made stand-in Sergio Ermotti permanent chief and brought forward the start date of chairman designate Axel Weber, in a move to reassure investors following the Swiss bank's $2 billion trading scandal. Ermotti, a 51-year-old from Switzerland's Italian-speaking Ticino region, was appointed interim CEO in September after Oswald Gruebel quit the bank over the trading losses. The appointment represents a rapid ascent for Ermotti, a former UniCredit deputy boss who joined UBS in April. Before UniCredit, he spent most of his early career at Merrill Lynch, where he rose to co-head of global equity markets.  The board made his appointment permanent after completing a comprehensive evaluation process. Former Bundesbank president Weber, who has pushed to join the bank as quickly as possible since the scandal, will be proposed as chairman at the annual general meeting in May, a year earlier than planned. UBS said its current board backed the bank's strategy to scale back its investment bank and focus on its core wealth management business, which will be detailed on Thursday at an annual investor event in New York. "A focused, less complex and less capital-intensive Investment Bank and our asset management business are also key elements for growing our wealth management franchise." Weber, who sources said had seen Ermotti as a fallback option and explored other candidates, welcomed the announcement, saying in a statement he would be in Switzerland in February to exchange ideas with his new colleagues and meet major clients.