The 26-year-old French international scrum half is in discussion with Saints over a new deal.
Although Woolf says he would like to keep the two-time Grand Final winning number seven – he is resigned to losing some of his squad due to the effects of the salary cap.
Woolf said: “We have a couple of blokes off contract this year, and everyone in our starting 17 at the moment is someone we would really like to keep and a priority.
“Theo in particular falls right into that category.
“He has been here at the club for six years, been our half back for the last two and a Premiership winning half back for the last two.