WASHINGTON (Reuters) - Special Counsel Robert Mueller and the team he assembled to investigate U.S. President Donald Trump and his associates have been funded through the end of September 2019, three U.S. officials said on Monday, an indication that the probe has funding to keep it going for months if need be.

FILE PHOTO: Special Counsel Robert Mueller (R) departs after briefing members of the U.S. Senate on his investigation into potential collusion between Russia and the Trump campaign on Capitol Hill in Washington, U.S., June 21, 2017. REUTERS/Joshua Roberts/File Photo

The operations and funding of Mueller’s office were not addressed in the budget requests for the next government fiscal year issued by the White House and Justice Department on Monday because Mueller’s office is financed by the U.S. Treasury under special regulations issued by the Justice Department, the officials said.

“The Special Counsel is funded by the Independent Counsel appropriation, a permanent indefinite appropriation established in the Department’s 1988 Appropriations Act,” a Justice Department spokesman said.

There has been increased speculation in recent weeks that Mueller’s team is close to winding up its work and is likely to deliver a report summarizing its findings to Attorney General William Barr any day or week now. Mueller’s office has not commented on the news reports suggesting an imminent release.

Representatives of key congressional committees involved in Trump-related investigations say they have received no guidance from Mueller’s office regarding his investigation’s progress or future plans.

The probe, which began in May 2017, is examining whether there were any links or coordination between the Russian government led by Vladimir Putin and the 2016 presidential campaign of Trump, according to an order signed by Deputy Attorney General Rod Rosenstein.

Critics of the probe, including Trump allies, have suggested the investigation is a misuse of taxpayer funds and should be wrapped up quickly.

Justice Department documents show that Mueller’s office reported spending around $9 million during the fiscal year which ran from Oct. 1, 2017 to Sept. 30, 2018. No figures are available for the current fiscal year.

Ninety days before the beginning of a federal government fiscal year, which starts on Oct. 1, special counsels such as Mueller “shall report to the Attorney General the status of the investigation and provide a budget request for the following year,” according to the regulations.

Department officials said that under these regulations, a special counsel should request funding for the next fiscal year by the end of June. It is not known if Mueller is preparing such a request for fiscal year 2020.

Russia has denied meddling in the 2016 presidential election. Trump has said there was no collusion between his campaign and Moscow, and has labeled Mueller’s investigation a “witch hunt.”