Xavi, who is with Spain at the FIFA World Cup, has been linked with a move away from Barcelona for the majority of this year, as the pace of La Liga appeared to get away from the 34-year-old midfielder at times last season.
While MLS has previously been mentioned as a possible destination for Xavi, Petrescu, who became Al Arabi's coach on June 5, claimed the veteran midfielder is on his way to Qatar in an interview with Romanian television station Digi Sport.
The former Romania international claimed he has spoken to Xavi on the phone from Brazil and could offer the Barcelona captain a salary of €8million per year.
"Xavi has signed a pre-contract with Al Arabi. It is likely that he has offers from other clubs too," Petrescu said.
"I told Xavi that if he is prepared to run and give everything for the team, he should come here.
"We are in direct contact with the player. He is currently in Brazil focusing on his job with the national team.
"I talked to him on the phone and I appreciate that he's an extraordinary man. If Xavi comes here, we'll be able to attract bigger names but I'm not prepared to disclose these names now.
"Naturally I would like to bring Xavi to our team. Al Arabi can give him €8m per year."
Petrescu added he is in discussions to bring a Romania international striker to Al Arabi but declined to name the targeted player.
Romania's current captain Ciprian Marica could be Petrescu's target, however, with the 28-year-old striker having been released by Getafe at the end of last season.
Marica has scored 28 goals in 71 appearances for Romania, while he managed five strikes in 24 appearances in all competitions for Getafe.
Al Arabi are seven-time Qatari champions but have not won the league since 1997, while their most-recent trophy was in the Qatar Sheikh Jassem Cup in 2011.
The Doha-based club finished fifth in the 2013/14 Stars League season, outside the AFC Champions League qualifying berths and 14 points behind champions Lekhwiya
