UPDATE 1-U.S. deficit estimate to be cut to $1.58 trillion

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WASHINGTON Aug 19 (Reuters) - The U.S. government's budget office will announce next week the federal deficit for fiscal 2009 will total $1.58 trillion, about $262 billion lower than a forecast in May, an administration official said on Wednesday.

A separate official from the Office of Management and Budget said spending in the year to Sept. 30 would total $3.653 trillion and revenues would be $2.074 trillion.

The decline in the size of the deficit, from an estimate in May of $1.84 trillion, would peg it at 11.2 percent of U.S. gross domestic product, the officials said.

The U.S. government, which has been spending broadly to fight a recession that continues to cut into tax revenues, posted a $180.68 billion budget deficit in July, a record for the month.

The Treasury said the July budget gap was the 10th consecutive monthly deficit and brought the fiscal year-to-date deficit to $1.267 trillion, more than triple the $388.61 billion deficit for the same period a year earlier.