APA Group has ratcheted up tensions with Brookfield in the takeover tussle for transmission grid owner AusNet, suggesting its giant Canadian rival needs its long eight-week due diligence period to nail down the funds for its $9.6 billion cash takeover offer.

In a move that raised eyebrows in Brookfield’s camp, APA described the Canadian firm’s funding for its bid as “uncertain”, while also claiming AusNet’s potential to grow would be enhanced under its ownership rather than Broookfield’s.