England produced their most fluent attacking display and ran up their highest total of the season as they scored five tries against France at Saint Nazaire.

Number eight Jamie Gibson (London Irish) struck twice in the first 12 minutes with centre Tom Casson (Harlequins) and wings Marcus Watson (London Irish) and Sam Smith (Harlequins) touching down in the second half.

Their lapses gave France a toehold in the game with scrum half Alexis Bales grabbing two tries and Lucas Dupont, Xavier Chiocci and Arthur Roulin getting over from close range.

But England's firepower all over the pitch was backed up by Tom Homer (London Irish), who was successful with five conversions and four penalties to add to his attacking incursions from full back.

England had needed to win by an unlikely 48-point margin to overtake table-topping Ireland and secure the U20 RBS 6 Nations title and finish in second place on points difference.

The visitors made three changes in personnel from last weekend's 27-6 win against Scotland with Homer returning at full back, Shaun Knight at tight head and Will Welch in the back row, with Stade Francais scrum half Charlie Davies on the bench for the first time.

Gibson gave them the perfect start with a try inside 60 seconds as he charged down Jean-Marc Doussain's attempted clearance and regathered to score.

He struck again 12 minutes later, having started the move with a lineout steal before Casson's 40m break cut France open down the right.

In between, though, France squeezed down a narrow blindside for Dupont to score, then took advantage of England losing the ball in their own 22 with a succession of drives before Bales stretched over.

Homer added penalties after 22 and 32 minutes, only for France to score a third try when loose head Chiocci was driven over.

Homer's third penalty of the half nudged the lead back up to 23-19, though, as France lost hooker Mickael Ivaldi to the sin bin for killing the ball in his own 22.

The interval was followed by England's best passage of the season - three superbly engineered tries in 12 minutes that finished France off mark the side out as a force to be reckoned with going into this summers's IRB Junior World Championship.

The first two were sweeping multi-phase attacks launched from their own 22, Watson touching down the first on the right, Casson striking with the second through the middle, and finally a turnover was put away in style as Clegg's instant cross-kick found Smith in space on the left.

France responded as the game opened up (both sides had a man in the sin-bin with Tanguy Molcard and Joe Marler yellow carded) with scrum half Bales chipping and chasing for a second try on the hour before Homer's fourth successful penalty pushed England 21 points clear.

The hosts scored a late consolation effort in the closing moments, Roulin forcing his way over with Gilles Bosch converting.

France U20: Julien Fritz (Lyon): Lucas Dupont (Grenoble), Benjamin Petre (Agen), Remi Lamerat (Toulouse), Jeremy Sinzelle (Toulon); Jean-Marc Doussain (Toulouse), Alexis Bales (Agen); Xavier Chiocci, Mickael Ivaldi, Gwendal Lamache (all Toulon), Jean Sousa (Lyon), Jean Souvent (Stade Rochelais), Arthur Roulin (Clermont Auvergne), Tanguy Molcard (Biarritz, captain), Antonie Erbani (Agen).

Replacements: Benjamin Geledan (Biarritz) for Ivaldi 37-47, Eddy Ben Arous (Racing Metro 92) for Chiocci 45, Kevin Gimeno (Beziers) for Sousa 73, Josselin Grange (Lyon) for Erbani 70, Jeremy Gondrand (Bourgoin-Jallieu) for Fritz 60, Gilles Bosch (Perpignan) for Doussain 48

Scorers: Tries: Bales 2, Dupont, Chiocci, Roulin. Conversions: Doussain 2, Bosch 2.

Yellow cards: Ivaldi, Mocard.

England U20: Tom Homer (London Irish); Marcus Watson (London Irish), Andrew Forsyth (Leicester Tigers), Tom Casson (Harlequins), Sam Smith (Harlequins); Rory Clegg (Harlequins), Sam Harrison (Leicester Tigers); Joe Marler (Harlequins), Jamie George (Saracens), Shaun Knight (Gloucester Rugby), Calum Green (Leicester Tigers), Charlie Matthews (Harlequins), Will Welch (Newcastle Falcons), Jacob Rowan (Leeds Carnegie, captain), Jamie Gibson (London Irish).

Replacements: Arthur Ellis (London Wasps) for George 74, Lee Imiolek (Sale Sharks) for Knight 60, Danny Wright (Gloucester Rugby) for Green 61, Jackson Wray (Saracens) for Welch 17, Charlie Davies (Stade Francais) for Harrison 50, Mark Atkinson (Sale Sharks) for Casson 61, Tom Catterick (Newcastle Falcons) for Watson 74

Scorers: Tries: Gibson 2, Casson, Watson, Smith.

Conversions: Homer 5. Penalties: Homer 4.

Yellow card: Marler