UPDATE 1-Obama admin: foreclosure prevention effort on track

(Adds highlights from prepared testimony, background)

WASHINGTON, Sept 8 (Reuters) - The Obama administration's effort to combat rising U.S. home foreclosures is on track to meet the goal of modifying more than half a million delinquent mortgages by Nov. 1, a senior administration official said.

In testimony prepared for delivery at a congressional hearing on Wednesday, Federal Housing Administration Commissioner Dave Stevens said mortgage servicers had extended more than 571,000 loan modification offers through August.

That figure was placed in brackets in the text of his testimony, suggesting the figure might not be final. The testimony was posted on the website of the House of Representatives Financial Services Committee.

About 360,000 modification offers have entered the 90-day trial period required before the modification can be made permanent, the text said.

Stevens said the administration was conducting a "high level review" of the housing rescue effort and was also exploring "programmatic options" to ensure signs of stabilization in the housing market are maintained.

In the prepared testimony, Stevens warns of increasing evidence of "material and growing" challenges in the multifamily mortgage sector that could have negative consequences for tenants.

Mortgage Bankers Association data show that first-quarter 2009 delinquency rates among securities backed by multifamily mortgages rose dramatically from the year-ago quarter, Stevens said.

Stevens said the administration was completing a "top to bottom review" of the housing department's multifamily initiatives in search of new alternatives to address the situation.

(Reporting by Tim Ahmann; Editing by Richard Chang)