Transport Scotland is to look into the possibility extending the Borders Railway, with links into the English network.
It is asking Jacobs UK to look at wider transport issues across the south of the country and expects a detailed response by the end of the year.
The findings will feed into the Scottish government’s nationwide strategic transport projects review.
Transport Minister Humza Yousaf said a commitment had previously been given to looking at an extension along with improvements on the A1, A7 and A68.
He said: “This study will take forward that commitment by considering how we improve accessibility in the Borders, link communities to key markets through strategic transport routes and identify where improvements to transport links are required.
“We want to build on the existing Borders railway by considering whether it should be extended to Carlisle.
“The study will also look at how we improve access from the Scottish Borders to key markets in to Edinburgh, Carlisle and Newcastle.”
He said Transport Scotland would work with partners to identify a “range of options” to be considered as part of the wider review.
“These options could include new rail services, improvements to existing road infrastructure and improved public transport provision.”