The Pentagon is notifying about 10,000 active-duty Army and Marine Corps troops and about 37,000 National Guard and Reserve soldiers that they will be sent to Iraq this year to replace those who will finish their duties, officials said Tuesday.

Up to 20,000 of the troops being notified would replace those soldiers who were due to come home in April but were extended by 90 days, according to local media reports.

The move means that the US military would keep the current level of 138,000 US forces in Iraq till at least the fall. The Pentagon had initially planned to cut the number of US troops in Iraq to 115,000 by this spring.

Defense Secretary Donald Rumsfeld extended last month the stay of some 20,000 American troops by 90 days at the request of General John Abizaid, commander of the US Central Command which is charge of US military operations in the Middle East.

At least 138 US troops were killed in Iraq in April as they confronted surging insurgency across the country.