Two UH-46 Sea Knights and two MH-60 Knight Hawks fly over Andersen Air Force Base, Guam, in this file photo.

The Obama administration is preparing to scale back a stalled U.S. military plan to relocate Marine forces from Japan to Guam by rotating thousands of Marines through foreign bases in Australia and the Philippines instead, according to a Bloomberg news report Friday.

The new administration plan calls for shifting about 4,500 Okinawa Marines to Guam – reducing the current plan by about half — and rotating about 4,000 more Marines through Australia, Subic Bay and possibly other bases in the Philippines and Hawaii, the news service said, citing anonymous administration sources.

The report comes after the U.S. inked a joint-basing agreement with Australia in November and last month acknowledged talks with the Philippines about hosting military forces again, nearly 20 years after the last U.S. base there was shuttered.

The U.S. Embassy in Tokyo declined to comment on the report and referred questions to the Department of Defense, which was not immediately available.

The U.S. and Japan are struggling to follow through with the 2006 agreement to move about 8,600 Marines and their families from Okinawa to Guam, which has been the centerpiece of a historic military realignment plan in the region.

The Senate has called the realignment plans unrealistic, unworkable and unaffordable, and Congress called for a review of basing plans in the region this winter and froze any funding this year for relocating the Marines. Sen. John McCain, R-Ariz., said in December that the plans could be modified with joint basing arrangements such as the one with Australia.

Meanwhile, Okinawa has vowed to block the plan due to a provision that requires the Futenma Marine Corps air station to remain on the island and be moved to a new facility built along a remote coastline by the Japanese government.

It was not immediately clear how administration plans might affect the Futenma relocation or the number of Marines who stay on Okinawa.

Read the Bloomberg story