A US businesswoman convicted of spying in China has been deported on Friday, 28 April, after being held for around two-years without any trial.

Sandy Phan-Gillis was taken into custody in March 2015 while she was leaving for Macau with a business delegation from Texas. Her husband, Jeff Gillis, said she was arrested on accusations of spying.

China had alleged that Phan-Gillis, who has Chinese origins but was born in Vietnam, visited the mainland twice in 1996 due to some intelligence work, Jeff Gillis said.

She was also accused of being associated with the US Federal Bureau of Investigation (FBI) to detain two Chinese spies in the US and turn them into double agents.

However, Chinese authorities have not provided any details of the charges against Phan-Gillis. Her lawyer also declined to give any information regarding the case, saying it involved "state secrets", Reuters said.

The deportation came after a court, on 25 April, ordered her extradition after awarding her a prison term of three-and-a-half years for espionage. Phan-Gillis reached Los Angeles on Friday after leaving from the Chinese southern city of Guangzhou.

"Sandy is overjoyed to be reunited with friends and family, and sends out her thanks to the many people who worked tirelessly for her release," her husband Jeff said in a statement.

The development came after US President Donald Trump met Chinese President Xi Jinping in Florida in early April. It was believed that the deportation would also help in strengthen ties between the two countries.

Meanwhile, according to the San Francisco-based Dui Hua Foundation, the process to secure the release of Phan-Gillis took place when US Secretary of State Rex Tillerson visited Beijing in March and negotiated about the deportation.

Sandy Phan-Gillis' deportation would help in strengthen the ties between US and China - Representational image REUTERS/Carlos Barria/File Photo