Sidwell is in the form of his career and has played in every league game for the Cottagers this season.
But the 30-year-old’s contract is up next summer and he has rejected an initial offer of a new one-year deal.
Instead, he wants another two years on top.
That would bring him into line with fellow midfielder Parker, 33, who joined this summer from Tottenham on a three-year contract.
For the big stories and the banter follow us on Twitter: @tribalfootball