Umno president Ahmad Zahid Hamidi has confirmed former minister Mohamed Nazri Abdul Aziz's claim that the party's MPs signed a statutory declaration (SD) empowering Zahid to seek new alliances with other parties, including the ruling Pakatan Harapan and Islamic opposition party PAS.

Zahid told the Malay Mail that all 51 of the party's MPs had signed the SD.

He also did not discount working with Harapan component parties even though Umno had been leaning towards PAS recently, stating that the "door is open".

Nazri had on Thursday revealed the existence of the SD in justifying his stance of not wanting Umno to contest against PKR president Anwar Ibrahim in the Port Dickson by-election.

The Padang Rengas MP said it was unwise to sour ties with PKR as it is now a major party in Parliament.

Mahathir had said that there was "no way" Umno would be accepted into Harapan unless their members individually quit Umno.

BN, and more specifically Umno, had in the last three by-elections in Sungai Kandis, Seri Setia and Balakong cooperated with PAS.

The former ruling coalition saw its first defeat in 61 years since independence during the May 9 general election.

Despite this, Umno remains the largest party in Parliament with 51 MPs, despite three having quit the party.