Newcastle United boss Rafa Benitez insists he's staying no matter the future of the club.

The manager has a strained relationship with owner Mike Ashley, who is in negotiations with financier Amanda Staveley and PCP Capital Partners, a Middle East and Chinese investment fund.

Asked if he would still be in charge this time next year if Ashley was unable to sell.

"I think so," the Spaniard said ahead of Saturday's visit of Watford. "I'm happy with this group of players, they're improving, they're learning.

"Was I disappointed after the lack of investment in the summer? Yes, but this is still a challenge for me."

Meanwhile, Benitez warned supporters that he will not have a significant increase in transfer funds when the club is sold.

He said: "Financial Fair Play rules do not allow you to spend massive money. If we have a change in ownership it will not make a big difference.

"We will not have too much money if it's a new ownership and, if it's the same ownership, the figures could be very similar."