The 25-year-old Benetton Treviso man picked up a calf injury in the European Cup defeat by Gloucester at the weekend.
And unlike team-mate Gonzalo Canale, who has been ruled out of the game against the world champions in Rome, Dallan is determined to play against England.
"In an agreement with the medical team, I prefer to wait until I fully recover from the calf injury, only then will I begin to run. I want to play against England," Dallan told the Federation's official website, www.federugby.it.
Dallan is unlikely to play in Saturday's 2004 All Star Game, which will see the Azzurri taking on the best foreign players of the Super 10 tournament in Treviso.
The good news for coach John Kirwan is the recovery of Italian lock forward Carlo Checchinato, who has began training after recovering from a knee injury.
And World XV coach Jannie Breedt believes his side will provide Italy with the perfect preparation for their RBS 6 Nations opener.
Coach Breedt told http://lire.datasport.it: "We will try to do the best as Italy's sparring partner. Our team will play like the classic Barbarians and will try to give the Azzurri real problems.
"I expect an intense game which will be good for (coach) John Kirwan's men before the RBS 6 Nations. We want to help Italian cause at the Six Nations but we also want to win this game."