The 25-year-old midfielder has not played for the Irons since the 5-0 defeat at Newcastle on January 5, having been in and out of the side because of injury.
It appeared the Swiss international, who arrived at Upton Park from Lazio in a £5million deal during July 2008, was all set for a transfer back to Italy as Fiorentina sporting director Pantaleo Corvino admitted he 'fitted their requirements'.
Is this the way to Florence? Valon Behrami wants a move to Fiorentina
However, the deal appears to have stalled and Behrami feels he has been left in limbo.
Second home: Switzerland international Behrami joined the Hammers from Serie A side Lazio
'Will I come to Florence? Good question. At the moment my arrival in Florence is far from certain,' Behrami told Italian newspaper Corriere Fiorentina.
'I am a little bitter, because I understand very little of this situation. It seemed all done and then.
'I did everything to come to Florence. Tomorrow is another day, let's see what happens.'
Behrami maintains the proposed move does not mean there is any rift with Hammers boss Avram Grant, who earlier this week finally received the public backing of the Upton Park board after intense speculation about his future.
The midfielder said: 'I have a good relationship with Avram Grant.
'The brake on my move to Florence is not down to him because he understood my feelings.'
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