The Spanish giants, who have been chasing Fabregas for several years, have bid ?25.5million, plus ?5m in add-ons.
Fabregas will then contribute another ?4.5m to the deal by giving up around ?900,000 per year in wages from his new deal.
Finally off? Ces Fabregas (right) looked unhappy in training this week
The latest move is set to bring an end to one of the longest-running transfer sagas and Fabregas could even be unveiled by the weekend.
The midfielder has made it clear this summer that he wants to finally rejoin the club he left as a 15-year-old boy.
Back then, Fabregas signed for the Gunners and within three years was a regular in the first team.
Although his loss is a huge blow, boss Arsene Wenger will be relieved to finally escape from the annual pressure of holding on to his captain.
However, he must now work on tempting Samir Nasri to stay at the Emirates despite Manchester City closing in on a deal to land the midfielder.
Another exit? Samir Nasri could now follow Fabregas out
City are willing to offer more than ?20m to sign the Frenchman, who would be available for nothing this time next year when his contract expires.
Arsenal fans, who have put up with six seasons without a trophy, have only seen Alex Oxlade-Chamberlain and Gervinho arrive in major deals this summer.
Wenger, who turned the Gunners into a force in English football in the 90s, is under pressure to end their long wait for silverware.
But with the threat of both Manchester clubs, Chelsea and a rejuvenated Liverpool, that task appears as tough as ever.
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