A Christian nurse is suing for unfair dismissal after she was sacked by a hospital trust for offering to pray with patients before operations.

Patients complained about Sarah Kuteh, who has 15 years of nursing experience, to the Dartford and Gravesham NHS Trust.

She was dismissed for breaching guidelines about discussing religion at work.

In a video about her case posted on the Facebook page of Christian Concern, she asks: "How could telling anyone about Jesus Christ really be harmful to any patient?"

Kuteh was responsible for pre-operation assessments of patients, which required them to fill in a form that included a question about their religion.

She said: "I discuss my religion with the patient and how I have found Jesus Christ and how much peace I have – especially when patients come to me feeling really, really devastated sometimes.

"I reassure them on the basis of the joy and peace I have found in the Lord."

After previous complaints from patients about inappropriate conversations about religion, she was warned about her behaviour. "The next day I got a letter and it stated I could have discussions with the patient or if the patient asks for it," she says, adding: "I'd always ask the patient if they were comfortable – and most of them were."

Kuteh was suspended in June and sacked in August following an investigation that heard a patient had complained she had given her a Bible she did not want and said she would pray for her. Another said she thought Kuteh was "preaching" at her.

A spokesman for Dartford and Gravesham NHS Trust said in a statement: "We have a duty to our patients to ensure that when they are at their most vulnerable, they are not exposed to the unsolicited beliefs and/or views of others, religious or otherwise.

"Following several complaints from patients and a warning which did not result in any change in behaviour, we feel we have acted appropriately in the management of this case."

The Prime Minister, Teresa May, said recently that Christians should feel free to speak about their faith at work.