Engineers will be working around the clock between Welshpool and Newtown on Saturday and Sunday to make emergency repairs to an embankment on the railway following storm damage caused by the recent weather.
Bill Kelly, route director for Network Rail Wales and Borders said: “The recent adverse weather has caused numerous issues all across the network.
"We are doing our best to make the necessary repairs as soon as possible and ensure the railway remains safe for trains to continue to run.
“I’d like to thank passengers and line-side neighbours for their patience as we carry out this emergency work and urge them to check before travelling."
A rail replacement bus service will be in operation.
Bethan Jelfs, customer delivery director for Transport for Wales Rail Services said: “Network Rail’s emergency repair work at Welshpool will impact on our services between Shrewsbury and Newtown over the weekend, with some bus replacements extending to Machynlleth, so customers need to be aware of how this may affect their travel arrangements.
“We are working closely with Network Rail to keep disruption to a minimum and I would like to take this opportunity in advance to thank our customers for their patience and understanding whilst these essential repair works are being carried out.”