PROVIDENCE, R.I. — Fleet-Norstar Financial Group said Monday its bad loans would increase at least $200 million in the first quarter, clearly showing the depth of New England’s banking troubles.

“They’ve been one of the most prudent lenders. They saw problems before others did and yet they’re still getting hurt,” said Thomas C. Ackerman, an analyst with Advest Group Inc.

Fleet, with $33 billion in assets, two-thirds of them outside the region, said non-performing loans would reach at least $600 million and could go higher as a result of an examination now being conducted by federal regulators.

At $600 million, that would be about 2.6 percent of Fleet’s loan and lease portfolio of about $22.5 billion. That still is lower than the industry average of about 3 percent, said Robert W. Lougee Jr., Fleet’s director of communications.

“We have not estimated what the reserve might be or what the earnings might be,” he said.

The company’s first-quarter earnings report could be delayed past the April 18 annual meeting, depending on the outcome of the examination, Lougee said.

“Certainly for a company of the quality of Fleet, this is a manageable level” of non-performing loans, said James J. McDermott Jr. of Keefe Bruyette & Woods.

Until federal regulators complete their examination, however, “the stock is probably under a cloud,” he said.

The stock closed at $21.25, down 62.5 cents, on the New York Stock Exchange.

Fleet also said it would sell about half its approximately $500 million credit card portfolio to Norwest Corp. of Minneapolis. The sale and a change in investments for the corporation’s pension plan are expected to produce a one-time gain of $90 million before taxes for the first quarter, Fleet said.

The bank decided not to become a major credit card processor and would confine its credit card operations to customers who have other accounts, Lougee said.

Despite Fleet’s decision to increase its non-performing loans by a third, “that’s certainly not the nosebleed levels you’re seeing at other banks,” said James Winchester of Mabon Nugent & Co. “You do have one of the best managements in the business there. It’s going to be a tough time for anybody with New England exposure.”

The bad loans had been identified “largely on our own” and not at the insistence of federal regulators, Lougee said.