Warren Buffett bought about $2.5 billion worth of Citigroup. If you're looking f...

The Oracle of Omaha has had a busy quarter.

According to his latest 13F filing, Warren Buffett has deployed roughly one-third of his cash into new investments during the first three months of the year.

As always, Buffett’s biggest swings are noteworthy. However, his decision to sell most bank stocks while adding Citigroup (C) to Berkshire Hathaway’s (BRK) portfolio is puzzling Wall Street.

Here’s why this contradiction has caught so much attention.

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Buffett loves banks

Buffett is deeply familiar with banking and financial services. He believes the business is relatively straightforward and can be extremely lucrative if managed well.

“If you can just stay away from following the fads, and really making a lot of bad loans, banking has been a remarkably good business in this country,” he told Berkshire Hathaway investors in 2003.

What about the 2008 Global Financial Crisis? Buffett went on a shopping spree during that time, picking up stakes in JP Morgan (JPM) and Goldman Sachs (GS).

For several years, major banks have been the biggest holdings in the Berkshire portfolio. In 2009, he even said Wells Fargo (WFC) was his highest-conviction investment.

“If I had to put all my net worth in one stock, that would’ve been the stock,” he told Berkshire shareholders.

Catching Buffett on the rebound

This year, Buffett has completely exited all these investments. Only a few banks remain in the portfolio.

That doesn’t mean the love affair with financial services is over.

In fact, Buffett added a new bank to his collection this year: Citigroup. During the first quarter of 2022, he added 55 million shares of Citigroup to the Berkshire portfolio.