MPs have stepped up their criticism of the interest rates being charged by credit card companies.

The bosses of Capital One, Lloyds TSB and HBOS, who together control a large part of the market, were grilled over the case of a 21-year-old deaf man who is believed to have committed suicide after building up debts of £15,000 with HBOS subsidiary Halifax bank.

Liberal Democrat MP Norman Lamb said: "His father feels convinced that the size of the debt was part of the pressure that he was under and he feels passionately about the need to lend responsibly."