As Japan works to recover from the devastating earthquake and tsunami that struck last week, Freddie Mac says the global instability caused by the natural disaster has driven mortgage rates to their lowest point in months.

Freddie Mac says during the week ending March 17, the average interest rate for a 30-year fixed-rate mortgage fell from 4.88 percent to 4.76 percent.

In addition, the rates for 15-year mortgages declined to 3.97 percent from 4.15 percent the previous week - the lowest point since December.

"With the crisis in Japan, investors rushed to buy the security of U.S. Treasury bonds , which lowered its yields and other interest rates as well," said Frank Nothaft, vice president and chief economist, Freddie Mac. "This allowed fixed mortgage rates to drift lower this week."

Falling interest rates may lead to more borrowers refinancing in the coming weeks as mortgage costs go down. According to the Mortgage Bankers Association, refinance applications applications jumped to their highest point in three months during the week ending March 11.