(Updates with suit against Bendigo and Adelaide Bank, changes...

(Updates with suit against Bendigo and Adelaide Bank, changes slug)

Sept 4 (Reuters) - Australia's corporate regulator said on Wednesday it had sued Bank of Queensland (BOQ) and Bendigo and Adelaide Bank (BEN) over what it called unfair loan contracts for small businesses.

The Australian Securities and Investments Commission (ASIC) alleges in separate lawsuits that between November 2016 and June 2019 both banks set unfair terms for contracts they had entered into with small businesses.

The contracts included clauses that gave the lenders leeway to vary the terms and conditions without the consent of the borrower and to declare the loan a default even if the borrower had met their obligations.

Bank of Queensland said it had started a review of all the small-business lending contracts it had entered into since November 2016 and would compensate any wronged customers.

Any compensation will not impact Bank of Queensland's financial position, it added.

Bendigo and Adelaide Bank said the loan contracts came under its Delphi Bank and Rural Bank brands during the period, and it was cooperating with the ASIC.

ASIC has taken a more aggressive approach toward corporate litigation after it was criticised during a public inquiry into financial-sector wrongdoing last year for being too soft on alleged misconduct.