Albion hope to keep the experienced striker next season after winning promotion to the Premier League but prolonged discussions over a new deal have failed to reach a successful conclusion.
The former Sunderland star, who will turn 35 before the start of the new campaign, is looking for a two-year deal which would probably take him to the end of his career.
But Albion have so far only offered Phillips a one-year deal and that stand-off has seen a number of other clubs, including Derby, Barnsley, QPR and Leeds, linked with his signature.
Gary McAllister's ambitious approach is likely to be more seriously considered by the striker if his negotiations with West Brom come to nothing.