Saturday's Triple Crown triumph has seen Ireland move above England in the latest IRB World Rankings.
Winger Shane Horgan's 78th-minute try against the English earned a second Triple Crown in three seasons for Eddie O'Sullivan's side, and also consigned Andy Robinson's England to sixth in the rankings.
Due to their 13-10 defeat at the hands of Scotland in Rome on Saturday, Italy drop down one place to twelfth. France, who beat Wales 21-16 in Cardiff to claim the 2006 RBS 6 Nations title, stay third, while the Welsh remain in seventh.
IRB WORLD RANKINGS: (Issued March 20)
(1) NEW ZEALAND 93.32 RATING POINTS
(2) SOUTH AFRICA 88.76
(3) FRANCE 85.95
(4) AUSTRALIA 83.93
(5) IRELAND 82.74
(6) ENGLAND 80.59
(7) WALES 78.64
(8) SCOTLAND 77.70
(9) ARGENTINA 75.16
(10) SAMOA 73.97