The British housing market has "deep, deep" structural problems which pose the biggest current risk to the economy, Bank of England governor Mark Carney said. "The issue around the housing market … is there are not sufficient houses [being] built," Carney told Sky television. He said the number of large mortgages being approved was rising and more houses needed to built. "We're not going to build a single house at the Bank of England," he said. "We can't influence that. What we can influence … is whether the banks are strong enough. Do they have enough capital against risk in the housing market?" Carney said the bank could also check lending procedures "so people can get mortgages if they can afford them but they won't if they can't". "By reinforcing both of those, we can reduce the risk that comes from a housing market that has deep, deep structural problems." Carney said there was evidence that large mortgages, where homebuyers are given loans up to four times their salaries, were on the rise again. "We don't want to build up another big debt overhang that is going to hurt individuals and is very much going to slow the economy in the medium term," he said. "We'd be concerned if there was a rapid increase in high loan-value mortgages across the banks. We've seen that creeping up and it's something we're watching closely." Last week, the bank played down the chances of an imminent rate rise despite fears of a growing house price bubble. "The biggest risk to financial stability, and therefore to the durability of the expansion, centres on the housing market and that's why we're focused on that," Carney said.