According to Channel 2 report which aired Monday, the reported investigation has already begun in Israel and authorities are seeking to carry out judicial inquiries abroad.
Police and the State Attorney's Office have reportedly been carrying out the investigating.
Netanyahu has charged back that "there is no basis to the claims."
In June, Netanyahu's office rejected allegations that French billionaire Arno Mimran transferred millions of unreported funds for the premier's 2009 election campaign.
The PMO called Mimran's testimony an "absolute lie that has no basis," and said that Netanyahu did not receive any money from Mimran to finance his campaign.
Netanyahu's office admitted to receiving $40,000 from Mimran in 2001 that went toward Netanyahu's fund for public affairs, while he was a "private citizen." The PMO said that the money went toward Netanyahu's public diplomacy efforts for Israel, and its handling was conducted in accordance with the law.Herb Kenion contributed to this article.