Barclays Bank on Tuesday posted mixed first-quarter profits, hit partly by slumping income at its investment banking division, ahead of a strategy update which is expected to axe jobs.Net profits rose 15 percent to £965 million ($1.6 billion, 1.2 billion euros) in the three months to the end of March from the level a year earlier.That was helped by falling costs and lower impairment charges, Barclays said in a results statement.However, adjusted pre-tax profit -- stripping out fluctuations in the value of the bank's own debt and provisions to reimburse customers for mis-sold products -- sank by 5.0 percent to £1.69 billion in the quarter.The drop in adjusted profits was sparked by a "significant decline" of 41 percent from the lender's Fixed Income, Currencies and Commodities (FICC) business.Operating expenses were cut by 16 percent to £4.435 billion amid the group's ongoing restructuring programme.The results were published ahead of the group's strategy update to be presented on Thursday by chief executive Antony Jenkins, who is widely expected to outline fresh job cuts.British media have also reported that Barclays could announce the creation of a so-called "bad bank" in order to offload non-core assets"A continued strong momentum across our retail, cards and corporate banking franchises, all of which generated higher returns year on year, offset by a significant decline in FICC income within the investment bank, resulting in group adjusted profit before tax decreasing 5.0 percent," Jenkins added in Tuesday's statement."UK Retail, Barclaycard and Corporate together drove approximately half of the group's income this quarter and we remain well positioned to benefit from further improvements in the economic environment."Turning to this week's strategy update, Jenkins added that it will "address issues underlying the performance challenges we have recently experienced, including positioning the investment bank for the new operating and regulatory environment".Meanwhile, there were no additional provisions for the compensation of customers who were mis-sold payment protection insurance - a scandal that has blighted Britain's banks in recent years.Turning to the outlook, Barclays added that it remained "cautious about the trading environment".It added: "We remain focused on structurally reducing the cost base in order to improve returns.