An NRL chief executives meeting in Sydney has endorsed a plan for the veteran-player allowance, which currently stands at $100,000 per club, to be doubled from next year.

Clubs become eligible for the exemption if they have had a player, or players, in their ranks for eight years or more.

They can use the $200,000 towards paying one nominated player and will receive a salary-cap discount for the same amount, allowing them to spend that money on other players.

The spending capacity of clubs next season will be further bolstered by an increase in the salary cap, from $4.2 million to $4.3 million, and an expansion in the marquee-player exemption from $150,000 to $300,000.

Newcastle have only two players who qualify for the long-service allowance - Simpson and skipper Kurt Gidley.

Simpson, whose NRL career with the Knights kicked off in 1999, is off contract at the end of the season and facing an uncertain future.

The former Test forward has not played since Newcastle's loss to Wests Tigers on May 21, after which he underwent extensive knee surgery.

Knights officials have reserved a decision on his future until he returns to the field and they are able to assess his form.

Simpson's hopes of securing a new deal could hinge on whether St George Illawarra back-rower Jeremy Smith accepts the three-year deal Newcastle have offered him.

The 25-year-old Kiwi international has a year to run with the Dragons but they have reportedly agreed to grant him an early release if he can sign a long-term deal elsewhere.

Smith has been been linked to Cronulla but the Knights are quietly confident he will agree to their terms, possibly by early next week.

"I would suggest we're getting there, but it's still yet to be confirmed," Knights coach Rick Stone said.

"The next couple of days will tell."