The average long-term U.S. mortgage rate climbed this week to its highest level in nearly 12 months, pushing up borrowing costs for prospective homebuyers at a time when rising oil prices are already squeezing household budgets

Rates have risen for two consecutive weeks and have been hovering around the 6.5 percent level since mid-May.

The average long-term U.S. mortgage rate climbed this week to its highest level in nearly 12 months, pushing up borrowing costs for prospective homebuyers at a time when rising…