PARIS — The financial crisis that began in the United States spread to many corners of the globe. Now, the American bailout looks as if it is going global, too, a move that could raise its cost and intensify scrutiny by Congress and critics.

Foreign banks, which were initially excluded from the plan, lobbied successfully over the weekend to be able to sell the toxic American mortgage debt owned by their American units to the Treasury, getting the same treatment as United States banks.

On Sunday, the Treasury secretary, Henry M. Paulson Jr., indicated in a series of appearances on morning talk shows that an original proposal introduced on Saturday had been widened. “It’s a distinction without a difference whether it’s a foreign or a U.S. one,” he said in an interview with Fox News.

The prospect of being locked out of the bailout set off alarm bells among chief executives of overseas banks whose American affiliates also hold distressed mortgage-related assets, like Barclays and UBS. The original text provided access to the $700 billion bailout for any financial institution based in the United States.