JD(U) spokesperson KC Tyagi said the party will approve the proposal in the meeting in Patna.
The JD(U) national executive will be chaired by the party chief Nitish Kumar and a decision to join the NDA government will be formally announced, he said.
Mr Tyagi's comments came following Mr Shah's invitation to Kumar to join the ruling alliance. "I met JD(U) president Nitish Kumar at my residence yesterday. I invited JD(U) to join the NDA," Mr Shah said in a tweet.
The Bihar-based party is also likely to join the Narendra Modi cabinet whenever a reshuffle takes place. Asked if the party would join the Modi cabinet, a JD(U) leader said such a decision would be "natural". "When we are together in government in Bihar, it is only natural that our party joins the Union government," he said.