Everton's costings for their new stadium have ballooned "significantly".
The Toffees still intend to move in time for 2022-23, having signed a lease at Bramley Moore Dock. The move was expected to cost an original £300m.
Elstone insisted they will cover the soaring costs.
He said: That funding target has escalated significantly and has occupied much of our efforts of the past 12 months.
"The premium for the waterfront site, an ambitious capacity that we will test with more rigour, a design we can all be proud of and the simple but painful impact of inflation, have all contributed to an increased overall cost and a funding target which continues to grow.
"It's a challenge that has always had the full support of Liverpool City Council and throughout 2017, we have been totally committed to finding a funding arrangement that works for the club and the city."