(ShareCast News) - The UK will challenge any attempt by international regulators to ask smaller banks to hold more capital against the residential mortgages on their books, Sky News reported.The broadcaster cited a letter sent on Tuesday by the Prudential Regulatory Authority´s chief Andrew Bailey to several small lenders.That was in reaction to a consultation paper published by the Basel Committee last week, Sky said.As of 09:13 shares in Aldermore were rising by 6.79% to 217.9p on the back of the news and those of One Savings Bank by another 3.06% to 350.4p.