"Absolutely. They've [Pakistan] shown time and time again that in this part of the world they're certainly a force in all formats so it will be an exciting one day competition.
"There are a lot of new faces and a lot of fresh faces so all the guys are looking forward to the games coming up."
The Black Caps, like most international sides, are putting a strong emphasis on one day cricket ahead of the World Cup early next year but Williamson believes there is plenty to be gained from the two T20 games.
"Any time you represent your country is an honour and a privilege and deserves the respect of the match that's played so there's very much a focus going into these T20 games.
"But there's that World Cup in the back of everyone's minds and one day cricket is a priority for most teams.
"Although it's a change in format it's also still cricket and there's still a lot to gain from these two T20's going into the one day series."
Although the Black Caps had taken great confidence out of their third test victory Williamson says the different make-up of the T20 and ODI teams means the y are facing new and different challenges.
"The test was a nice victory and you have some good feelings coming after victories but we have a very different side and it's a very different format," he said.
"Our focus is very much with what is in front of us and it's a very different challenge. So although it is nice to come off the back of a victory it's probably not very relevant going into T20 cricket with a very different side.
"It's sort of slightly different on this occasion where a few players have gone home and are rested and it's quite a different squad.
"Coming off the back of a win is always a nice feeling but it's very different personnel so the challenges that lie ahead are very different as well.
"The team is fresh and looking forward to it. They know that the challenge ahead is quite a steep one with a very strong Pakistani side so all the guys are excited to take on that challenge."
Williamson acknowledged Wednesday's funeral for Australian cricketer Phil Hughes had given the players some closure after a difficult and emotional week and their focus was now shifting back to the on-field challenges that await them.
"There's perhaps little bits of closure with the funeral and the thoughts with the people closest to Phil.
"The boys, obviously it's still reasonably fresh and they're still thinking of those bits and pieces but at the same time are looking forward to the cricket coming up."
He is looking forward to the chance to lead the side in Brendon McCullum's absence and is determined to maintain the side's winning course.
"It's very exciting and a privilege to be able to captain the side. There are a lot of leaders and a lot of young talent but I'm sure that throughout these five games we can start to challenge and put the performances on the board."