Investec analysts on Friday retained a 'sell' recommendation for Lloyds Banking Group stocks, but upgraded Barclays to 'buy'.The two UK banks have been making headlines in recent months for alleged financial wrongdoings. Barclays was hit by a string of scandals in relation to LIBOR rigging, while Lloyds was fined for delaying payment protection insurance compensation to customers. However, they received two very different reviews from Investec on Friday.Investec told investors to "get back on it" and buy stocks in Barclays as the bank undergoes a massive restructuring to boost results. "We remain unwilling to join the growing ranks of the "Barclays £4 club" - on a 12 month view, we do not regard 1.1 x 2013 estimated tangible net asset value as a credible aspiration in a transitional year," the broker said in response to brokers who gave the bank a 400p target price. "However, we do see the post-results retracement as overdone in both relative and absolute terms. After huge out-performance up to and including February 12th, Barclays has been the sector's worst performer since then. We tweak our forecasts to capture benefit from the £/$ collapse, and upgrade back to 'buy'." Nevertheless, Investec told investors to "stand well clear" of stocks in Lloyds and issued a target price of 46p.Looking ahead at the future of Lloyds, Investec said it expects the bank to announce an underlying profit before tax of £2.4bn for 2012 which translates to an attributable loss of £1.8bn. "Despite a return to modest profitability in 2013 estimate, we then expect tangible net asset value to fall to 55p. Lloyds already trades on 1.0x 2013 estimated tangible net assets value which cannot be justified by our return on equity forecasts of 2.0% in 2013, 6.0% in 2014 and 8.0% in 2015."RD