Citi says it's time for investors to load up on shares of BP . Analyst Alastair Syme upgraded the oil stock to a buy from a neutral rating, saying BP offers a more favorable valuation than its European peers and "decent growth characteristics." "Growth is one aspect that we believe BP can start to differentiate around versus large-cap European peers; we forecast underlying growth almost 2x that of closest peer SHEL," he wrote, highlighting particular strength in the company's upstream business through several liquified natural gas projects. Citi upped its price target on shares of the U.K.-based company to 5.40 pounds sterling, suggesting the stock could rally 18%. U.S.-listed shares of the stock have surged more than 24% this year and rose 4% in the premarket. "We see market rotation into energy equities as having further to run, even though names in our US coverage already sit at all-time highs," Syme wrote. "History says energy equities usually perform well in an earnings recession, Citi's base case for 2023." — CNBC's Michael Bloom contributed reporting.