While Donald Trump's surprise victory in the U.S. presidential campaign helped Wells Fargo (WFC) - Get Report stock pare some of the slide spurred by its bogus accounts scandal, the rally may have started to fizzle.

Shares of the San Francisco-based bank have fallen 1.1% this week, giving up part of a double-digit gain after Trump was elected president, as a federal regulator tightened its oversight. Wells Fargo will now be required to obtain approval from the Office of the Comptroller of the Currency before hiring board directors and senior executive officers or paying severance packages, rules from which it had previously been exempt, the agency said Monday.

Additionally, the bank's applications to open or relocate branches will no longer receive expedited treatment, the comptroller's office said.

While the regulator didn't specify the reasons for the changes, its altered attitude is "very bad news for Wells Fargo," Richard Bove, a Rafferty Capital Markets analyst, said in a phone interview. It signals that the comptroller's office, which has often been protective of the banks in its purview, may be willing to leave Wells Fargo more vulnerable to punitive actions in the states where it operates.

The more stringent federal regulatory requirements "are not a result of any new event or issue," Wells Fargo said in a statement. "This will not inhibit our ability to execute our strategy, rebuild trust, serve customers, and continue to operate the company for the benefit of all stakeholders."

The comptroller's action exacerbated a week of gloomy news for the bank, which reported Thursday that account openings in October dropped 44% from the previous year. They were also 27% lower than September as customers reacted to Wells Fargo's $185 million settlement that month over the opening of as many as 2 million unauthorized accounts.

The revelations prompted two Congressional hearings and led to the abrupt retirement of CEO John Stumpf as well as a spate of investigations and the loss of lucrative government deals.

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October was the first full month of data following the scandal, and bank executives "recognize we have work to do," said Mary Mack, the new community banking chief. "We are focused on strengthening our relationships with existing customers and building new ones with potential customers."

Credit card applications dropped 35% from September and were down 50% from a year earlier, Wells Fargo said.

There was some good news for the company, however.  Account closures rose only 3% in October from the prior month and customers continued to use their accounts and cards while maintaining their balances. Customer loyalty scores averaged 73.9%, down slightly from the prior year, but up from their lowest levels.

"Although the stability is reassuring, Wells Fargo is not out of the woods," Allen Tischler, a Moody's analyst, said in a note to clients. "In addition to ongoing regulatory investigations, lawsuits, political pressure and its board's own investigation, Wells Fargo's reputation with customers remains impaired."

The company continues to lag behind the broader KBW Bank Index, which has benefited from President-elect Trump's call for a temporary moratorium on new financial regulations and his support for repealing the Dodd-Frank Act, which tightened Wall Street rules after the 2008 crisis.

Wells Fargo's stock has dropped 3.9% this year to $52.22, while the S&P 500 has gained 7.8% and the KBW Index has surged 18%.