He is a member of the United Malays National Organisation (UMNO), a component party of the Barisan Nasional (BN) coalition.
His defection from the People's Justice Party (PKR) back to the United Malays National Organisation (UMNO)—days after he had defected the other way earlier—helped cause the collapse of the Pakatan Rakyat (PR) government of which PKR was a component party.
[1] In the 2008 election, the Pakatan Rakyat (PR) coalition took power in Perak, consigning Nasarudin's UMNO to opposition for the first time in the state's history.
On 25 January 2009, Nasarudin announced his defection to PKR, thus boosting the Pakatan Rakyat's narrow majority in the assembly.
Joined by three other Pakatan Rakyat MPs, the defection gave the UMNO-led Barisan Nasional coalition the numbers to return to the state government.