Phillips, capped 82 times by Wales and with five test appearances for the British and Irish Lions, has suffered behind a struggling forward pack and makes way for Rhys Webb.
"I thought Rhys played excellently for the Ospreys at the weekend and he comes in and gives us a different dimension and it's a great opportunity for him," coach Warren Gatland said on Wednesday.
Williams was injured tackling Ireland's Brian O'Driscoll in Dublin while Davies, who suffered a chest injury in the November test against South Africa, has failed to recover sufficiently despite returning for club side Scarlets, meaning North shifts infield and Liam Williams starts on the wing.
Luke Charteris returns at lock after missing the last match with a hamstring injury.
"Luke has been working really hard over the past couple of weeks and it's a big boost for us that he is back," New Zealander Gatland added.
"George moves into the midfield and he brings great footwork to the role and we were impressed when he went there against Australia in the autumn. His partnership with Jamie will be important as we look to stop the directness of France and Mathieu Bastareaud."
Wales have looked off the pace in this season's championship, with the Ireland defeat preceded by a sluggish performance in a 23-15 win over Italy.
Gatland acknowledged a win was required to keep them in the hunt for the crown, as well as boosting their confidence ahead of the final two matches against England and Scotland.
"Friday is a massive game for us," he said.
"As a squad we have a huge amount of experience in this tournament and we will be calling on that this weekend. We see the game as a huge opportunity for us to put things right."
France have made a perfect start to their campaign, narrowly beating England in their first match before easing to a comfortable 30-10 win over Italy in their last outing.
They have made one change to their starting lineup for Friday's clash, with flanker Wenceslas Lauret called up to earn his sixth cap as a replacement for Bernard Le Roux, who is recovering from a blow to the head.
Team: 15-Leigh Halfpenny, 14-Alex Cuthbert, 13-George North, 12-Jamie Roberts, 11-Liam Williams, 10-Rhys Priestland, 9-Rhys Webb; 8-Taulupe Faletau, 7-Sam Warburton, 6-Dan Lydiate, 5-Alun Wyn Jones, 4-Luke Charteris, 3-Adam Jones, 2-Richard Hibbard, 1-Gethin Jenkins
Replacements: 16-Ken Owens, 17-Paul James, 18-Rhodri Jones, 19-Jake Ball, 20-Justin Tipuric, 21-Mike Phillips, 22-Dan Biggar, 23-James Hook
(Reporting By Josh Reich in London; Editing by Rex Gowar)
