NHS bosses have moved to reassure patients over treatment availability, following the closure of consultant-led paediatric and maternity services at a general hospital.

Both Darlington Memorial Hospital and James Cook University Hospital, in Middlesbrough, said they had capacity for an influx of patients from North Yorkshire as the paediatric unit at the Friarage Hospital, in Northallerton, halved its opening hours for children today.

In addition, parents are being asked to only take children to the Friarage's accident and emergency department if they have a minor injury.

On Monday, a midwife-led unit, for pregnant women who are medically fit, have had a normal pregnancy and are at low risk of complication, will open at the hospital.

It has been estimated births at Northallerton will drop from 1,200 deliveries a year to 500, placing additional burdens on the neighbouring hospitals.

In recent weeks, both the Darlington and Middlesbrough hospital have vehemently countered claims that their corresponding units were understaffed.

The changes follow an acrimonious battle spanning nearly three years in which campaigners, including Richmond MP William Hague, pressed Hambleton, Richmondshire and Whitby clinical commissioning group (CCG) to find a way of preserving the services.

CCG spokesman Dr Charles Parker said: "We have been working closely with the trust over the last few months to ensure a smooth transition to the new service, and we have every confidence that they will achieve this."

A County Durham and Darlington NHS Foundation Trust spokesman said a recent national survey by the Care Quality Commission of women’s experiences of maternity services, ranked its maternity services among the top ten in England.

He said: "We look forward to welcoming families from North Yorkshire to Darlington Memorial Hospital, and would like to give assurance to patients of our commitment to providing safe staffing levels and the high quality of our women’s and children’s services."

A spokesman for South Tees NHS Trust, which runs both the Friarage and James Cook hospitals, said it had no concerns about staffing levels.

Gill Adgie, North of England head for the Royal College of Midwives (RCM), said it was working to make the Friarage unit a success and research showed women often prefered the more homely environment of a midwife-led unit and often had better outcomes and fewer interventions, such as caesarean sections.

Ahead of the changes, a new bus service has been launched to take people from Friarage Hospital to the James Cook site, while there are plans in place to provide a shuttlebus to take patients between the hospitals.