With each team getting one point, England qualified for the Super Eight stage, thanks to their superior net run-rate. England have a net run-rate of -0.452, better than Ireland's -3.500 after the two group matches.
Hosts West Indies [ Images ] have already qualified as the top team from the Group D.
Put into bat, England went off to a dismal start but Eoin Morgan's [ Images ] determined 37-ball 45 helped them eke out a moderate 120 for eight.
Morgan, who struck five fours, found good support from Luke Wright [ Images ] (20). The duo came together when the team was struggling at 49 for four and added 41 runs for the fifth wicket partnership to give a timely recovery.
Rain halted the match soon after Ireland started chasing the victory target of 121. They were four for no loss in 1.2 overs when the match was halted due to heavy downpour.
Though the proceedings resumed under a laden sky after almost half-an-hour, Ireland could add only 10 runs in 13 balls before the heaven again opened up and the players ran for cover.
Ireland suffered their only loss during those few minutes of play when opener Paul Stirling (0) fell prey to Ryan Sidebottom [ Images ] in the second over.
Ireland was 14 for one in 3.3 overs, with captain William Porterfield (4 n.o.) and Niall O'Brien (9 n.o.) on the crease when the play was halted for the second time.
Earlier, Ireland bowlers put up a disciplined performance to make the English batsmen's life miserable on a damp pitch, with Boyd Rankin (2/25) and Kevin O'Brien (2/22) scalping two wickets each.
Opener Michael Lumb (14) started on an attacking note by cracking a four off paceman Rankin's first ball through the fine-leg region.
But England suffered first loss when pacer Kevin O'Brien removed Lumb in the first ball of the fifth over, with Rankin pouching a good low catch at short fine-leg region.
Lumb's opening partner Craig Kieswetter (13) also returned to the dugout in the next over when the Englishman went for a close single but wicket-keeper Niall O'Brien found him short of the crease.
All of a sudden England found themselves in a spot of bother when captain Paul Collingwood [ Images ] also fell prey to Trent Johnston and returned without adding anything to the board.
Collingwood failed to manage a moving delivery off the pacer and the ball kissed his willow before flying to Botha who made no mistake.
Kevin Pietersen [ Images ] (9) teamed up with Morgan when England was struggling at 32 for three.
Kevin O'Brien struck for his second wicket just when the duo were trying to give recovery. Pietersen could not manage a rising delivery off the pacer as his lofted pull found John Mooney in deep square-leg area.
Dismissals at regular intervals arrested the run-rate of England, who were 49 for four after 10 overs.
Morgan and Wright teamed up at a time when reaching 100 was looking improbable for England with Ireland bowlers maintaining good line and length.
But the duo negotiated the bowling attack patiently and added 41 runs before Wright was removed by Rankin in the 16th over with Porterfield taking the catch.
Morgan, who fell to Andre Botha [ Images ] in the last over, however, ensured that England cross the 100-run mark.