Rail passengers will face longer journey times and travel disruption "until early June" after the Oxford to Didcot line was closed by a sinking bridge.

Network Rail has said the line which links Oxford to London Paddington and services to the West Country and Wales will re-open by June 10 at the very earliest.

Since the line first closed last Monday, April 4, Network Rail said engineers have been “working round the clock” over the Easter weekend to "install a temporary structure that will stabilise the viaduct at Nuneham".

READ MORE: No update on Nuneham viaduct rail line until engineers finish checks

Engineers first raised the alarm when they detected significant movements of the viaduct, which crosses the River Thames between Culham and Radley.

Previously, the national rail’s operator said the line was likely to remain closed until at least the end of this month.

A Network Rail spokesman said: "We are sorry for the inconvenience this issue will cause as we work to make this viaduct safe for passenger and freight trains to run again."

Network Rail has promised to reveal more detailed plans on Wednesday, April 12.

READ MORE: Oxford prepares for major Botley Road closure on April 11

Rail replacement buses have since replaced train services between Oxford and Didcot Parkway stations and rail passengers are experiencing lengthy queues for these buses.

Passenger Natasha Jacoby, who resorted to using a rail replacement bus from Oxford to Didcot, said she had suffered significant delays on her trip to London.

She said: “The closure was a big surprise when I got to the station and I had no idea it was going to happen.

“It is obviously a disruption and is causing a huge amount of havoc."

READ MORE: The Botley Road closure - what we know so far from Network Rail

The travel chaos is set to get considerably worse tomorrow when Botley Road’s six month closure starts to allow work to begin on Oxford station’s £161 million improvement scheme.

The work includes rerouting utility cables, creating a new western entrance for the station and replacing the rail bridge.

With Botley Road closed from Tuesday, April 11 until October, heavy congestion is expected on the surrounding roads.

READ MORE: Waitrose not expecting Botley Road closure to 'impact stock'

A revised timetable is currently being drawn up by Great Western Railway, Cross Country and Chiltern Railways for the duration of the closure.

In response to increased demand for its Oxford to London Marylebone service, Chiltern Railways is advising people to only travel if necessary.

CrossCountry trains are currently operating a full service north of Oxford and a limited number of trains will serve the line between Didcot and the south coast.

Great Western Railway services between London, Oxford and the North Cotswolds are also affected with services terminating at Oxford; as well as the Didcot Parkway and Oxford shuttle.

Freight trains will continue to operate on alternative rail routes, including via Acton in West London.