According to London media, the North-East trio are rivals for the player who snubbed Newcastle last year.
Middlesbrough and Sunderland are among a host of Premier League clubs chasing the 25-year-old, with Aston Villa believed to be favourites to land him.
But even a bid of £4m from Villa Park is likely to prove insufficient, with the managerless Blues holding out for £6m, despite signing the player from Reading on a free transfer last summer.
However, Sidwell says he is keen to remain in west London and prove his credentials at Chelsea.