The Toffees rejected a new formal offer of about £45m from Chelsea for academy graduate Gordon earlier this week.
The 21-year-old made his Everton debut in January 2020 and signed a five-year contract eight months later.
"I don't want to talk about hypotheticals. He has got a huge value to the team and to me. We are not looking at it as 'where can we go with this deal?'
"We know his value but he's a big player for me and the team. You can't ask me to assure anything, it'll be naive of me to assure anything," he said.
"I can't assure I'll be here by the end of the window."