Johor Umno chief Mohamed Khaled Nordin said today that the decision of BN component parties in Sarawak to quit the coalition is a blow to the formation of a two-party system.

"Even though Johor Umno believes that it was done with due consideration and reasoning, such a move indirectly frustrates efforts to improve our democracy and the formation of a two-party system," he said in a statement.

Yesterday, Parti Pesaka Bumiputera Bersatu (PBB), Sarawak United Peoples' Party (SUPP), Parti Rakyat Sarawak (PRS) and Progressive Democratic Party (PDP) announced their exit from BN.

The four parties formed their own Sarawak-based coalition named Gabungan Parti Sarawak.

The move was another blow to BN, which now only has four component parties left compared to the 13 it had going into the 14th general election.

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In his statement, Khaled criticised the parties for quitting the coalition despite having been elected on a BN ticket.

"They were elected in their capacity as BN representatives. By leaving BN, they have betrayed the people's mandate given to them as BN representatives.

"It goes against the wishes of the people who want them to serve under the banner of BN," he said.

In the May 9 general election, Sarawak BN won 19 out of the 29 parliamentary seats in the state – though this was a drop from the 25 it won in the preceding election.

The coalition also won 72 out of 82 seats in the 2016 state election.

Pakatan Harapan and its allies swept into power in the general election, winning 122 of 222 parliamentary seats.

However, Harapan's main rival BN immediately began to disintegrate following its defeat.

According to Khaled, the decision of the four parties to leave BN also does not bode well for national integration.