The England international was ruled out of the team's upcoming festive fixtures with a hamstring injury but, despite asserting that the layoff is a "massive blow", Allen has appealed to the rest of the squad to minimise the loss of their skipper.
Speaking to The Mirror, the Welshman said: "It is going to be a massive blow for us to lose Stevie.
"Obviously he's a key player for us and our leader. People have to step up and show we can cope with that loss."
The Reds, who sit third in the Premier League table, five points adrift of Arsenal, travel to White Hart Lane for a clash with Tottenham Hotspur on Sunday.