Changes to the current salary cap were approved at a meeting on Wednesday, empowering English clubs to add a second marquee player to their squads for the start of next season.
The new recruit must not have played in the Premiership for the past 12 months, stopping teams stealing players from their domestic rivals.
His wages would fall outside of the cap, which is set to rise above its current £5million limit, and it is hoped the move will help Premiership clubs hold onto their prized assets.
Saints, who brought in Lions stars George North and Alex Corbisiero last summer, currently spend as much as they are allowed to and opted to use their funds to retain all of last season’s double-winning squad.
But they are keen to add more firepower to further enhance their chances of competing with Europe’s elite, and Mallinder will be given the go-ahead to bring in another stellar signing.
“We’ve been party to those negotiations and because we’re profitable, we’re in that great position that we can afford to spend more than the salary cap,” said Hewitt. “We only spend up to the salary cap now but we could go a little bit further if the cap is increased, which is what is being done.
“We were in favour of it and we’ve said to Jim to look at using that money. He has (already been told to start identifying targets).”
Hewitt expects to have the deal - and more contract renewals - tied up by Christmas as Saints continue to plan for next season, which will start after the Rugby World Cup.
“We’re in the period now as we were last year where we’re renewing the contracts that need renewing,” said Hewitt.
“We’re talking to agents, going through those negotiations and these days, in this modern world, players don’t just come to you - their agents punt them around.
“We’re talking to all the agents all the time, we’ve told them what our likely requirements may be and we’ll be making those announcements around Christmas time.”