Griffiths has scored 13 goals for Wolves this season after spending the last two years back in Scotland on loan at Hibernian.
Speculation has claimed the 23-year-old has struggled to settle back at Molineux, but Wolves boss Jackett has no intention of letting the Scotland international go.
"There's no way that's the case," said Jackett in the Express & Star following the reports that Griffiths is unsettled.
"He's a big part of things here and we're looking to improve our striking department if we can. Letting Leigh Griffiths go would not improve it.
"He's very much part of my plans here and however I decide to use him, whether it's from the start or after everyone has been running around for an hour, he can be a big contributor for us, as he has been so far this season."
Jackett is also weighing up a permanent deal for Jacobs, who has made six appearances for Wolves since joining on loan from Derby County last month.
"I do like the player so we will see," added Jackett. "It is something we have talked about internally.
"He is a player I am impressed with and at 22 he has a good base of experience with 160 League games. That's a good platform to move forwards in his career.
"We haven't spoken to Derby yet so we don't know if we can do something. There's nothing set up but as a coach and as a club we've been impressed with what he has done."