RIYADH, 19 September — Saudi surgeons successfully separated Malaysian Siamese twins, who were born conjoined at the stomach, at King Abdul Aziz Medical City here on Tuesday night.

"The operation, carried out with Saudi competence, was successful," Dr. Abdullah Al-Rabeea, deputy executive director of health affairs at the National Guard, told the Saudi Press Agency.

Prince Abdullah, the regent, financed the operation on four-and-half-year-olds Mohammed and Ahmed, which was estimated to cost SR1.5 million. The prince had asked the Saudi Embassy in London to send the twins from London to Riyadh for the operation.

Rabeea, a consultant for pediatric surgery, said the operation was performed without any problems.

"The team faced some difficulties when temperature of Ahmed increased to 39 degrees C during the operation," he pointed out.

"Both the boys are in stable condition by the grace of God," Rabeea, who led the team, said and commended the efforts of his team members.

As many as 41 doctors, nurses and paramedical staff took part in the complex operation.

A website of the hospital said the operation began at 9.45 a.m. on Tuesday. By 3 p.m., doctors finished abdominal adhesions and division. They completed angio chest wall separation by 6 p.m., it said.

According to Rabeea, the twins were to remain in the intensive care unit for about two weeks and under observation for about two to three months. Doctors have said the twins would be able to lead a normal life after the operation.

The Siamese twins, accompanied by their father Roush ibn Abdullah Rahman, 31, and mother Aysha arrived in the Kingdom by the end of last month.

Rahman thanked Prince Abdullah for his humanitarian gesture. He also praised the expertise of the medical team, which conducted the operation.

The team included experts for anesthesia, pediatric surgery, plastic surgery, pediatric urology and pediatric orthopedics.

After separating bowel and liver, the team completed urological, genital, pelvis and chest separation.

The multidisciplinary team had met several times to review the diagnostic studies on separating the twins safely. The clinical and diagnostic tests showed that Ahmed and Mohammed were joined at the chest, abdomen and pelvis. Both of them had normal head and upper extremities. However, each of them has only one lower limb and they share a third abnormal limb.

The internal organs showed a combined liver, and distal small intestine and colon. There was an overlap over the urinary and genital systems.

A number of diagnostic tests had been conducted on the twins before the operation. They included tests on liver and kidney functions, total body x-ray, multi-slice CT scan, MRI and angiography.