England head coach Eddie Jones says there is a huge amount of improvement to come from the new Six Nations champions.
Having taken over after England's disappointing World Cup campaign last autumn, Jones has guided the team to four wins from four matches in this year's championship.
They have already secured the Triple Crown and Six Nations title and will complete a first Grand Slam in 13 years if they can overcome France in Paris on Saturday evening.
"The most exciting thing is that we are only touching the surface now," said Jones. "We have had the team, literally, for six weeks. In six weeks, we have made some improvements, but there is a lot more to go individually and collectively as a team."
England clinched the title when France lost in Scotland on Sunday, but Jones says celebrations were muted because of the intense desire to complete the Grand Slam.
"We had a couple of beers last night very quietly, the guys just sat around," he said. "I think everyone is so keen to win the Grand Slam.
"We set out at the start of the season to be the most dominant team in Europe and to do that we need to win the Grand Slam. It has only been won 12 times by England in their whole history, so to be the 13th side would be a great honour."
England had to endure a nervy finish against Wales at Twickenham on Saturday, eventually holding on to win 25-21, having been 25-7 in front with just five minutes remaining.
Jones said: "We got a little bit too defensive. Obviously, we had one man in the bin for the last 10 minutes. Credit has got to go to Wales, they have been one of the top sides in Europe for the last five or six years.
"They have got some iconic players and they played well those last eight minutes and with a lot of freedom. It's always easy to win a game when you have lost a game.
"The reality was, they had lost the game, and it was easy for them to play catch-up rugby. We should have dealt with it better and we will learn that in the future."