Behrami says he is willing to help his international midfield partner settle in England.
Behrami has become well accustomed to his international midfield partner, with both players contributing to Switzerland's 1-0 win in their Euro 2016 opener with Albania on Saturday.
Having already experienced the rigours and demands of Premier League football with West Ham before joining the Hornets, Behrami is well aware of what it takes for a player to succeed in England's top division, and is under no doubt that Xhaka will be a hit in North London.
However, he insists that Arsenal fans may need to be patient with the 23-year-old and give him time to settle into life in England.
He told ESPN FC: "Everybody needs time and he will need time as well, but he is a great player.
"He's a top player and he's going to go to play in a team which is good for his quality because he likes to play the ball and he's quite technical.
"And he can do both sides. He can win the ball and he's got good tackling skills. I think he's a great signing for Arsenal and for him as well it's a great move."
With Watford and Arsenal's training grounds so close to each other, Behrami is even prepared to lend his own helping hand to Xhaka's career in England.
He added: "The training grounds are close so I'm going to help him with what he needs to settle down, and I think he's going to have a great season in the Premier League."
Arsenal needed more quality in the centre of the park and manager Arsene Wenger moved quickly to rectify that this summer with the addition of the promising Xhaka, with more new signings expected to follow in due course.