The Preferred bidder for the new Wembley stadium, Bovis Lend Lease/Multiplex, is about to submit a final estimate that will break the client’s £316m ceiling.

A scheme insider said: “The bid will not be in line with the client’s estimate of £316m and where it goes from here is up to them. There comes a point when you simply have to put in your best offer and that is what we will do within the next few days.”

It is understood that the client and the contractor are still about £15-20m adrift in their estimates.

As Building revealed last week, the scheme is undergoing design changes in a bid to get the cost down to £316m.

However, the insider said: “We’ve come up with a price which we think is realistic. Hopefully it will result in further negotiations with Wembley National Stadium Limited but ultimately it’s up to them.”

WNSL declined to comment.