Although they start their three-match series in Auckland on Friday with Pakistan ranked sixth and New Zealand seventh, they are equal on 114 points.
But with only four points separating the top seven teams, if either side can win all three matches they will replace the West Indies at the head of the table, the International Cricket Council (ICC) said in a statement.
If the series is settled 2-1, then the winner will leapfrog South Africa to fifth position.
The New Zealand-Pakistan series features the return to international cricket of convicted Pakistani spot-fixer Mohammad Amir who has served a jail term and five-year ban from the game.
However, the New Zealanders, fresh from a 2-0 Twenty20 series win over Sri Lanka, maintained that the appearance of Amir was not an issue.
“That is not something that worries us,” all-rounder Grant Elliott said. “All we are concerned about is how good someone is on the cricket field.
“What I do know about Mohammad Amir is I played him in 2009 in the Test series and he was a very quick bowler then. It will be interesting to see how he comes back from what has happened.
“As a cricketer you need to focus on what is in front of you whether you are bowling or batting without that mentality it is very difficult to perform under pressure.”
With a number of Twenty20 Internationals to be played in the lead up to the ICC World Twenty20 India in March, there is likely to be plenty of reshuffling at the top of the world rankings.
The biggest player movements in the latest list are Afghanistan’s wicketkeeper-batsman Mohammad Shahzad and fast bowler Dawlat Zadran who both make the Twenty20 top 10.
Shahzad has jumped 12 places to eighth on the batting list after scoring 151 runs in two matches against Zimbabwe, while Zadran claims the bowling eighth spot after claiming five wickets in the same series. (Courtesy AFP)