The event is being hailed as a "historic sod turn" of the $9.3 billion Melbourne to Brisbane rail line.

Mr Morrison will be joined by Deputy Prime Minister Michael McCormack and Finance Minister Mathias Cormann to spruik the "game-changing infrastructure".

But a long-time promoter of the project Everald Compton said on Wednesday that ceremony is "odd" considering a first sod event took place in 2001.

Mr Compton says there is a large stone and plaque in place to commemorate the event.

But Mr Morrison said the "corridor of commerce" will provide new investment and export opportunities opened up by the free trade agreements.

"Inland Rail will connect rural and regional Australia to millions of customers at home and overseas through key domestic and rapidly expanding international markets," he said.

"It will also drive significant investment in the communities themselves through the creation of around 16,000 direct and indirect jobs, and a $16 billion contribution to the national economy."

The Parkes-to-Narromine section, which is expected to create around 200 jobs, is one of 13 projects forming the 1700km Inland Rail line.

Inland Rail is the largest freight rail infrastructure project in Australia, with the aim of operating in 2024/25.

Construction will begin in Parkes and progress north towards Narwonah, about 8km south of Narromine, and is expected to be finished by mid-2020.

Australian Associated Press