Israel's financial watchdog says Prime Minister Benjamin Netanyahu improperly used state funds for his family, following complaints by the opposition.
State Comptroller Joseph Shapira found "excessive" sums had been spent by Mr Netanyahu and his wife, Sara, on food, furniture and gardening at their state residence and private home.
Some of the evidence has been passed to the attorney-general for investigation.
Mr Netanyahu promised to implement the recommendations to curb spending.
But he also criticised the "ongoing media campaign" surrounding the report, which he said was aimed at toppling him.
"There is absolutely no indication of any assault on the public's integrity and certainly no indication of any criminal transgressions," he stressed.
The report was published a month before an early general election, in which Mr Netanyahu will be seeking a fourth term in office.
Mr Shapira's long-awaited report said the taxpayer's bill for maintaining the prime minister's official residence in Jerusalem and private home in Caesarea more than doubled between 2009 and 2011, but was halved back to around its original level in the two years that followed.
It identified some examples of what it called expenditure that was "inconsistent with the basic principles of proportionality, sensibility, thrift and efficiency".
They included a $23,000 (£15,000) total bill for takeaway food deliveries in 2011 to the prime minister's official residence, where the staff included a cook.
The report also found clothing claims were two-and-a-half times the allocated budget and said cleaning bills at the residences were "very big" and "excessive".
Employees at the prime minister's office were reportedly sometimes forced to pay out of their own pockets for Mr Netanyahu's personal expenditures, and were not reimbursed.
The report also detailed bills for calling out an electrical contractor on Yom Kippur, the most sacred day in the Jewish calendar, when all work in Israel generally ceases.
The BBC's Kevin Connolly in Jerusalem says Mr Netanyahu's supporters portray the allegations against him as the work of a disgruntled former employee taken up by a largely hostile media.
They argue that there is nothing in the report which should outrage Israeli public opinion.
But, our correspondent adds, the prime minister's problems with the allegations are not entirely over.
The state comptroller left two issues to be examined by Attorney-General Yehuda Weinstein.
One is an allegation that Mr Netanyahu's wife kept refunded deposits paid on recycled bottles bought with public money to entertain guests.
The other is a story that garden furniture bought for the official residence ended up at their private home.