Under Friday’s agreement, Likud is to merge with the New Right, the party launched less than a year ago by Mr Bennett and Ayelet Shaked.
New Right’s 3 MKs will join Likud, raising its seat tally to 35 and making it the largest party in the Knesset.
According to Haaretz, a Likud statement said: “Bennett agreed that in case a new government is set up, such as a broad unity government or a narrow government, a different person will be appointed for the role of defence minister.
“The two also agreed that the Likud and New Right will immediately form a joint faction in the 22nd Knesset and are committed to operating together as a joint faction throughout the tenure of this current Knesset.”
It comes hours after Blue & White leader Benny Gantz, who is currently trying to form a coalition government, said he did not believe Likud wanted to form a national unity government.
It is not clear if Ms Shaked, a former justice minister, will be offered a role.