Dr Benjamin Carson, chief of pediatric neurosurgery at Johns Hopkins Children's Center, was flown in after Abu Dhabi Crown Prince Mohammed bin Zayed Al-Nahyan agreed to bear the costs of any operation, the BBC reported Monday.
New Delhi's Apollo Hospital officials are expected to announce this week whether the operation will proceed.
The most significant problem facing surgeons is the fact the girls share an artery that carries blood to their hearts and a blood drainage vessel in the brain, doctors told the BBC. In addition, Farah has two kidneys while Saba has none and will require a kidney transplant.
Carson was the lead neurosurgeon of a 70-member team that separated 7-month-old German twin boys in 1987, the BBC reported. In 1997, he and a team of 50 doctors separated 11-month-old Zambian boys, both of whom survived.
The specialist was assisted in at least three other attempts to separate conjoined twins, including the unsuccessful 2003 operation on 29-year-old Iranian twins.