WASHINGTON, March 16 (Reuters) - President Donald Trump is asking Congress to give the Pentagon about $2 billion for a "flexible" fund to use against Islamic State over the next six months, as his administration weighs changes to the U.S.-led campaign against the militant group.
Trump is also seeking to upgrade long-underfunded facilities at the U.S. military's Guantanamo Bay detention center in Cuba that Trump's Democratic predecessor, Barack Obama, unsuccessfully sought to close during his eight-year administration.
"It doesn't seem like we are going to close it anytime soon," John Roth, the acting Pentagon comptroller, told a Pentagon news briefing, explaining the move.
The proposals were part of a $30 billion supplemental request to Congress to add more money to the Pentagon's budget during the government's ongoing fiscal year, which began under the Obama administration and ends in September.
It includes plans to crank up U.S. funding for the fight against Islamic State militants for items like high-tech bombs and defenses against insurgents' drones, bringing overall spending on the campaign to the highest level yet, the Pentagon said.
"This will likely be our largest request," Roth said.
One analyst called the $2 billion flexible spending request a Pentagon "slush fund," and many lawmakers were expected to be reluctant to loosen oversight over how the Pentagon spends money.
What Trump's additional funding might mean for America's evolving war strategy against Islamic State in the coming months was not immediately clear.
But the request comes as U.S.-backed forces in Iraq and Syria are entering a critical phase in their campaign to retake Islamic State's two biggest cities of Mosul in Iraq and Raqqa in Syria. Trump's administration is weighing deployment of more U.S. troops.
The heads of the top U.S. congressional committees that oversee the Pentagon have criticized Trump's 2018 budget request, saying even more money was needed.
"It is clear to virtually everyone that we have cut our military too much and that it has suffered enormous damage," said Republican Representative Mac Thornberry, chairman of the House of Representatives Armed Services Committee.
Todd Harrison at the Center for Strategic and International Studies think tank in Washington questioned whether Trump's budget wish list could muster enough support among Democrats, whose votes would be needed to sign off on the spending bills given the slim Republican hold on the Senate.
Trump said during the election campaign that he not only wanted to keep the Guantanamo Bay detention center open but "load it up with some bad dudes."
Trump's $5.1 billion "overseas contingency operations" request included a provision for $1.1 billion in additional funds for a range of Pentagon projects, including "planning and design of construction projects in support of Detention Operations at Guantanamo Bay, Cuba."
The prison, which was opened by Republican President George W. Bush to hold terrorism suspects captured overseas after the Sept. 11, 2001, attacks came to symbolize harsh detention practices that opened the United States to accusations of torture.
Obama reduced the inmate population to 41, but fell short of fulfilling his promise to close the jail.
The 2017 request would also hike spending for the broader Defense Department over the next six months, with $24.9 billion more sought to "readiness needs" after years of complaints over congressionally imposed spending caps.
Lockheed Martin would be one of the biggest beneficiaries of that proposal. Some $13.5 billion would be spent on more military hardware, including five F-35 warplanes as well as Army Blackhawk helicopters made by Sikorsky Aircraft, a Lockheed subsidiary.
Trump also wants 12 interceptors for the THAAD missile defense system. The United States is now deploying THAAD in South Korea in response to North Korea's ballistic missile and nuclear tests.
Boeing would also gain with $2.4 billion for an additional 24 of its F/A-18 E/F jet fighters.
A further $7.2 billion would pay for things like military training, cyber and intelligence capabilities and support for weapons systems. (Additional reporting by Idrees Ali and Matt Spetalnick; Editing by Peter Cooney)