Earlier this month, HSBC announced that it would match the interest rate for two years of borrowers coming off fixed rate deals.
Commenting on the move, Mr Johnson said: "The HSBC offer is a very competitive one but so are many of the products offered by building societies.
He added that the firm's move was "what you would expect in the competitive mortgage market that we've got, where providers actually offer different products that will appeal to different customers".
Research released by the Financial Services Authority in June last year found that around 1.4 million people are expected to come off cheap fixed rate mortgage deals in 2008.
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