The former Blackburn Rovers and Stoke City midfielder, who has completed 90% of his passes this season, had been banished to train with the reserves having fallen out with former manager Eduardo Berizzo in November.
N’Zonzi, 29, had looked certain to leave Sevilla in the current transfer window, but the Frenchman may find himself back in the first-team squad when Sevilla play Cadiz in the Copa del Rey on Wednesday.
He has been involved in first-team training with his teammates for the first time in over a month, with former Fiorentina and AC Milan boss Montella set to take charge of his first Sevilla game after having been appointed on 28 December.
“N’Zonzi is fine. He is training well. He is an important player,” Montella is quoted by Spanish outlet El Desmarque.
“Normally, I do not like to announce the training before, because my intention is to officially announce the team first as always, [but he] is available for tomorrow and for the derby.”
Pressed on what the player’s immediate future holds, Montella added: “I do not know. I’ve talked with him. I have seen [his] attitude after being around the team. I do not know if he’ll will remain here until the end of the season, because I’m not in his head. ”
Berizzo’s departure came just days after the Argentine returned from prostate cancer surgery, with Sevilla without a win in three La Liga games.
N’Zonzi originally signed for Sevilla from Stoke in 2015, playing 108 times for the Spanish club so far.
West Ham interested in Steven N’Zonzi
West Ham manager David Moyes has confirmed he has been keeping track on N’Zonzi’s situation in the hopes of bolstering the club’s midfield during the transfer window.
The Hammers had tried to sign William Carvalho from Sporting Lisbon during the summer window, and could look to the Portuguese once again, but Moyes has already admitted N’Zonzi would be an ideal buy if available.
“I think he’s somebody who would be of interest to us if he came on the market,” Moyes said last month, as reported by the Telegraph.
“I wouldn’t say that about others, but he’s not playing for some reason at Sevilla – albeit the manager’s gone, so maybe that changes the situation there. Overall, it’s not something I can say I’ve done anything with.”
N’Zonzi is also admired by former West Ham manager Sam Allardyce at Everton, who originally brought the Frenchman to the Premier League with Blackburn.
Allardyce previously stated: “I would take Steven N’Zonzi tomorrow.
“He is one of my better buys in my lifetime, only €650,000 from France to Blackburn Rovers.
“He became young player of the year and player of the year in his first season at Blackburn Rovers when we finished 10th.
“He was a terrific pinch out of the French leagues and has gone on to do terrific things in his career ‘For me, knowing him from that age and knowing him now, yes I would like him but with the amount of midfield players I have at the moment I’d have to move some player out to bring a player like Steven in.”