The NRL has announced it will take action to protect players and staff of the Newcastle Knights who have not been paid by the club.

The Knights are controlled by Nathan Tinkler's business group - Hunter Sports Group - and the league said on Friday it had learned the club had failed to pay the salaries of at least 20 players and staff.

NRL chief executive, David Smith, said in a statement that the league would take whatever action was necessary to protect those affected.

The league's head of club services, Tony Crawford, said: "The actions of the Tinkler-controlled Knights towards players and staff are completely unacceptable and will not be tolerated.

"The NRL will be assessing all options to bring this to a resolution in the interests of the Knights, staff, our fans and the broader Rugby League community."

Last month Hunter Sports Group failed to meet a bank guarantee deadline as part of its ownership agreement.

The NRL has been leading discussions between Tinkler's group and the Knights Members Club about the future operations of the Knights.