BN communications director Shamsul Anuar Nasarah has criticised a viral copy of a letter of undertaking purportedly requiring Umno candidates to back party president Ahmad Zahid Hamidi as prime minister – calling it fake.

"It is confirmed that this 'Aku Janji' document that is going viral is false and not true. No such undertaking has been made.

"This is clearly a malicious effort from irresponsible parties and it is a plan to discredit Umno-BN during the general election," said Shamsul in a statement on the BN Comms official Facebook page.

Among the undertakings in the said document include pledges to support Zahid as prime minister, cease all investigations into party leaders and support government formation with any other party.

Gerakan Tanah Air (GTA) information chief Mahdzir Ibrahim recently questioned if the absence of animosity between PKR president Anwar Ibrahim and Zahid in the run-up to the general election might be an indication of a possible alliance after polling.

In his post, Shamsul, who is also incumbent Lenggong MP, urged Malaysians not to be influenced by the fake document.