Brennan Johnson roars for delight after putting Nottingham Forest 2-0 up against Derby County (Credit: Ritchie Sumpter)

Nottingham Forest are holding out for at least £20m if they are to allow attacking midfielder Brennan Johnson to leave this month.

The 20-year-old Nigel Doughty Academy graduate has been a key member of Steve Cooper’s squad this season as the Reds have shot up the Championship standings.

His six goals and four assists in 27 Championship appearances have drawn plenty of attention from potential suitors, including several Premier League sides.

Brentford had been leading the way in their interest of the young forward, but Sky Sports’ transfer centre claims Forest are after at least £20m before considering letting him depart the City Ground.

Such a high value will almost certainly test Brentford’s true interest in the midfielder; the Bees have also been heavily linked with a swoop for Danish midfielder Christian Eriksen.

Brentford boss Thomas Frank recently told BBC Sport: “The Championship is a good league to look at.

“I also think that when we were in the Championship that League One was a good league to look in, so that’s natural we do that.

“But obviously it’s also natural that we look in the European market. It doesn’t have to be Championship or England, it can be Europe.

“I think the Championship is actually too expensive. I think we pay too much for the quality of the players that you can probably get in Europe.”

Johnson has been in conversations with Forest over new terms for a number of months as his current deal is set to expire next summer.

Brennan, son of former Forest striker David Johnson, gave nothing away when interviewed on Sky Sports after his goal-scoring performance against Derby County at the weekend.

He said: “I’m not too sure. I’m loving my football at the moment.

“I’m very confident. All the boys are. I want to keep going and keep doing well.”