WASHINGTON » President Barack Obama will ask Congress for a hefty, almost 8 percent boost for the Pentagon, including $5.3 billion to equip and train Iraqi soldiers and moderate Syrian rebels to fight Islamic State militants in the Middle East.

Obama will ask for $534 billion for the core budget of the Defense Department — a $38 billion increase — according to "pre-decisional" Pentagon documents obtained Tuesday by The Associated Press. That means there could be some slight changes when the budget actually comes out Monday.

The Pentagon witnessed major budget cuts with the imposition of so-called budget sequestration in 2013 and has been held at a freeze since then. Military brass say the bleaker budgets have forced cuts in flying hours, troop training and maintenance of military equipment. The agency was due for just a $3 billion increase under caps set in a 2011 budget pact.

The increases are likely to find support among defense hawks on Capitol Hill, but Republicans controlling Congress are only in the early stages of figuring out how to pay for them. Simply taking the money from domestic agencies is sure to be opposed by the White House and could lead to gridlock in Washington.

The Pentagon anticipates cutting 15,000 Army soldiers this year and cutting another 25,000 soldiers by 2018 for an Army "end strength" of 450,000. The Navy would get an uptick of 5,600 sailors this year.

Most of the proposed increase would go to procurement of new war-fighting equipment and operations and maintenance accounts.

Another $51 billion would go for overseas military missions, including $43 billion for ongoing operations in Afghanistan and $3.8 billion to train Afghan security forces.

The Pentagon’s base budget is currently $496 billion, with another $64 billion for overseas missions.

The increases would allow for 57 new next-generation F-35 fighters, nine new ships and submarines, and construction of new long-range Air Force tankers.