A father of premature twins complained that a hospital in South China's Shenzhen city kept him and his wife from being with their newborn twin boys because the couple was not able to pay its 120,000 yuan ($18,900) bill.

Hospital officials say the parents have been kept from the boys not because of the bill, but because the ill babies aren't well enough to be exposed to bacterial infection.

The twin boys?- one of whom was diagnosed with an eye problem, and the other with hydrocephalus?- were hospitalized in Shenzhen Baoan Maternal and Child Health Hospital the second day after they were born, the twin's father, surnamed Liang, told local media on Tuesday.

Liang said his children were premature, born 10 weeks earlier than expected on June 23.

The couple, with a monthly income of 3,000 yuan, was not able to pay the bills. Liang said the hospital turned down their proposal to let the couple take the children home and have the parents pay off the debt later.

Liang said he and his wife could visit their children only at a fixed time every Thursday. He said he and his wife have never been able to hold the babies in their arms, and they are allowed to see them only through windows outside the ward.

Wu Zhijun, deputy director of the hospital's neonatology department, said on Aug 22 that both twins weighed about 1.3 kilograms after birth and suffered from preterm birth complications when they were hospitalized.

The twins are now in stable condition, and the hospital has not stopped treatment, although their parents have paid only 10,000 yuan to date, Wu said.

Wu said on the hospita's Sina Weibo micro blog that the children are in the intensive care unit, and the hospital cannot allow the couple to go inside because of the risk of bacterial infection.

He added that the twins' health is not good enough for them to leave the hospital, but if their parents insist, they can check out their children after following appropriate procedures.