Bank regulators approved Capital One Financial's acquisition of HSBC's $30 billion U.S. credit card business, the Office of the Comptroller of the Currency announced on Friday.

McLean, Virginia-based Capital One has been expanding through acquisitions recently and received approval from the Federal Reserve last month to acquire ING Groep NV's U.S. online banking unit in a $8.9 billion deal.

Capital One in August announced its plan to acquire HSBC's U.S. credit card portfolio in a $2.6 billion deal.

Consumer groups have been critical of Capital One's growth plans arguing that it has a spotty record in how it treats low-income customers and that the acquisitions will create another too big to fail bank.

Capital One has defended its record and highlighted the benefits the acquisitions will bring to new and existing customers.

Both the Fed and the OCC, which regulates national banks, extended initial comment periods on the deals in response to consumer advocates' requests to solicit more feedback.

Capital One shares ended the day up 0.8 percent to $49.82.

(Reporting By Dave Clarke; Editing by Tim Dobbyn)