"It's all done because we've shaken hands", he told reporters at Milan airport.
Pioli has since been confirmed as the new coach of Fiorentina on two-year deal. The 58-year-old guided La Maggica to a second place finish in last season's Serie A.
It had been widely expected given Spalletti's relationship with Inter sporting director Walter Sabatini, who also recently joined from Roma.
"Sabatini is a great person and also capable at his job, which makes things easy", said Spalletti. "It's still not official, but everything is going in this direction".
FILE - In this Tuesday, Oct. 22, 2013 file photo coach Luciano Spalletti shouts instructions from the touch line during the Champions League group G soccer match between FC Porto and Zenit Tuesday, Oct. 22, 2013, at the Dragao stadium in Porto.More news: Three men freed in Manchester terror probe
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Inter Milan has not won a trophy since 2011, when it captured the Club World Title.
Since then, the club has stumbled, so much so that Spalletti would actually become Inter's fifth coach in under a year.
Former coach Stefano Pioli was sacked three games before the end of a turbulent Serie A campaign which first saw Roberto Mancini resign two weeks before the start of last season, and his replacement Frank de Boer fired after 85 days, with Inter finishing the season under interim coach Stefano Vecchi.
They finished seventh, one point behind city rivals AC Milan and just out of the Europa League places, although Italy's quota of Champions League places will be increased to four from 2018.