Mining magnate and aspiring prime minister Clive Palmer says the Australian Labor Party's latest round of leadership speculation has been sparked by the growing threat of his Palmer United Party.

Mr Palmer, who was in Melbourne on Sunday to unveil 30 Victorian Palmer United Party (PUP) election candidates, told reporters that the current Labor leadership speculation was a direct response to the growth of his burgeoning political party.

Momentum: The Palmer United Party has now endorsed nearly 100 candidates. Credit:Justin McManus

''What it's really about is that Kevin Rudd would like to call the election early so he can stop our party from being registered federally,'' he said.

Mr Palmer said an early election in August would push forward the issuing of writs and hinder his party's ability to register.