The Obama administration is asking the largest mortgage finance companies to quicken the pace of modifying home loans and so help more troubled borrowers avoid foreclosure.

The largest 25 mortgage servicers should appoint a special liaison officer to work directly with government officials who are overseeing the program meant to save as many as four million borrowers from foreclosure, Treasury Secretary Timothy Geithner and Housing and Urban Development Secretary Shaun Donovan wrote in a letter.

There is a general need for servicers to devote substantially more resources to this program for it to succeed and achieve the objectives we all share, according to the letter to servicers written on Thursday.

Treasury will host a meeting with leading servicers July 28 to hear how the companies are expanding their aid programs and making sure that those seeking help are not improperly disqualified.

Recent data from bank regulators show a mixed picture for the industry in responding to the foreclosure crisis as more modifications are being offered at the same time that the number of tardy loans continues to grow.

Servicers made 185,156 loan modifications during the first quarter of the year, up 55 percent from the prior quarter, according to data from the Office of the Comptroller of the Currency and the Office of Thrift Supervision.

The report also showed that seriously delinquent mortgages, defined as loans that are 60 or more days past due, increased by nearly 9 percent from the prior quarter to 5 percent of all mortgages.

Leading banks, which are among the largest mortgage servicers, have defended their work to prevent foreclosures.

JPMorgan Chase & Co. says it approved 87,100 borrowers for lower monthly payments according to the Obama housing rescue plan.

Bank of America Corp has more than 7,400 associates fielding as many as 80,000 calls a day from customers seeking mortgage advice, said a company spokesman.

The letter asks mortgage servicers to expand their reporting of modification work, create stronger measurements for how they deliver help and cooperate with a fail-safe program that will make sure that eligible borrowers are not wrongly denied aid.

(Reporting by Patrick Rucker and Karey Wutkowski; Editing by Padraic Cassidy)