The U.S. government and the country's mortgage sector on Tuesday announced plans to help homeowners behind on their house loans.

Roughly four million U.S. homeowners were behind on their mortgage payments or in foreclosure in June, according to data from the Mortgage Bankers Association.

It was not immediately clear how many of those homeowners will be helped by the loan aid scheme.

To qualify, homeowners will have to be at least three months behind on their payments, and owe more than 90 per cent of the value of their house.

Anyone who does not occupy their home would not qualify for the aid, nor would borrowers who have gone into bankruptcy.

The government's plan would see interest rates cut so that borrowers would wind up not spending more than 38 per cent of their income on house payments. Another option is for loans to be extended from 30 years to 40 years, or for some of the loan principal to be deferred.

"Foreclosures hurt families, their neighbours, whole communities and the overall housing market," said James Lockhart, director of the U.S. Federal Housing Finance Agency. "We need to stop this downward spiral."

Lockhart's agency seized control of two mortgage finance companies, Fannie Mae and Freddie Mac, in September. Together, Fannie Mae and Freddie Mac own or guarantee almost 31 million U.S. mortgages, or about 60 per cent of all outstanding mortgages.

The new plan is hoped to be in place by Dec. 15.

With files from the Associated Press