Wales went ahead early on with a try from a driving line-out by No 8 Jon Fox, outside half Dan Jones converting. France came back with a penalty for Franck Pourteau but some good phase play enabled prop Keagan Bale to crash over from close range, Jones' conversion taking the score to 14-3. Pourteau nicked another penalty for his side just before the break but in the second half, France were the stronger side.
Spilt ball out of a scrum on Wales' line led to a try for No 8 Antoine Jelonch, narrowing the gap to just three points. Dan Jones gave Wales a cushion with a penalty soon after but it was Frnace's second try that made the difference. From a driving line-out, replacement scrum half Artur Retieres went over on 51 minutes, replacement Anthony Belleau scoring the winning conversion.
Wales had attacking opportunities but weren't clinical enough in their execution. Lewis said: "I can't fault the players' effort and the pack were excellent. But we needed to keep possession for longer periods in crucial areas and that's what let us down in the end. It was disappointing to lose, especially from a position where we were leading but we made it easier for France."
Wales play England next Sunday at the Gnoll (March 23, 1.45pm) and Lewis believes his side will need to be more efficient if they are to come away with a result.
"The challenge next week will be even bigger, especially up front, and England will ask more of our defensive patterns too. As a group, we learn a huge amount from games like this so we are looking forward to preparing for and playing England next Sunday."
Wales Under 18 squad which played France today (Chartres) and faces England next Sunday 23 March at the Gnoll (1.45pm):
Kieron Assirratti (Blues/ Coleg y Cymoedd/ Wattstown), Keagan Bale (Dragons/ Coleg Gwent / Caerleon), Robert Lewis (Blues/ St Peters / Coleg y Cymoedd), Leon Brown (Dragons/ Newport High), Harrison Walsh (Ospreys / Bishopgore / Mumbles), Liam Belcher (Blues/ Coleg y Cymoedd / Pontypridd), Dafydd Hughes (Scarlets / Llandovery College / Llandovery), Matthew Dodd (Ospreys / Olchfa / Dunvant), Seb Davies (Blues / Coleg y Cymoedd / Pentyrch), Calum Haggett (Blues / Coleg y Cymoedd / Gilfach Goch), Josh Middleton (Scarlets / Coleg Sir Gar / Kidwelly), Tom Phillips (Scarlets / Coleg Sir Gar / Llangennech), Jon Fox (Ospreys/ Gower College / Swansea), Harrison Keddie (Dragons / Coleg Gwent / Caerleon), Josh Cole (Ospreys / Neath Port Talbot College / Tonmawr)
Backs: Michael Hale (Blues / Glantaf / St Josephs), Owen Davies (Dragons / Monmouth Boys School / Oakdale), Kieran Hardy (Scarlets / Coleg Sir Gar / Pontyberem), Thomas Williams (RGC/ Rydal Penrhos / Newtown), Dan Jones (Scarlets / Coleg Sir Gar / Carmarthen Quins), Owen Watkin (Ospreys / Bridgend College / Bryncethin), James Whittingham (Blues / Cowbridge), Morgan Williams (RGC/ Coleg Llandrillo / Caernarfon), Rhys Gealy (Ospreys / YG Gwyr / Pontarddulais), Lloyd Lewis (Dragons / Ysgol Gwynllyw), Shaun Pearce (Scarlets / Glan y Mor / Bury Port)