The advocacy group which has campaigned for this work for nine years, since Labor first announced the planned upgrade in 2009, said "it's about time" and believe the upgrade will benefit the Sunshine Coast in ways never seen before.

Deputy Premier Jackie Trad and Transport and Main Roads Minister Mark Bailey announced funding for the Beerburrum to Nambour Upgrade on Saturday, which means more than $550 million in funding has been promised for the project, when factoring in the federal government contribution.

The project will see the duplication of about 20 kilometres of North Coast Line between Beerburrum and Landsborough, as well as the construction of more 'park and rides' and extra passing points.

The state government will cover 20 per cent of the cost, the federal government has promised to pay for 50 per cent, but both sides are still arguing over who should pay the other 30 per cent.

Ms Trad said the Coalition should pay because the track runs next to the Bruce Highway, which has always been subject to an 80:20 split where Queensland pays the smaller amount.

However, Rail Back On Track Sunshine Coast spokesman Jeff Addison said he could not understand why the state government would reject the 50-50 split offer from Canberra.

Mr Addison said the land and infrastructure was owned by the state, there had never been an 80-20 split over a state rail line before and the Sunshine Coast line had never received any federal funding.

He vowed to hold the state government to their word and said his reaction to the funding announcement was simply "Hallelujah".

"It’s about time the Sunshine Coast got a transport system appropriate for our size," he said.

"This will open a whole host of benefits and travel to the coast that we've never had before.

"The Sunshine Coast will get an extra 18 services per day, these are the services we need."

Ms Trad announced on Saturday that planning would continue during the 2018-19 financial year before the five-year construction period was set to begin in 2019-20.

"We need to respond to the need of a rapidly growing population ... this will be the duplication of the last single-track section on the south-east Queensland rail network," she said.

“The Beerburrum to Nambour Rail Duplication will deliver increased capacity, travel time savings for passenger and freight services, and increased reliability on the North Coast Line.

“It will reduce the competition between passenger and freight services, and enable vital public transport links to the rapidly growing Sunshine Coast area.

“This project wouldn’t be able to happen if the Palaszczuk government hadn’t kickstarted it by doing the business case and submitting to Infrastructure Australia last year after three years of inaction by the former LNP Government.”

Transport and Main Roads Minister Mark Bailey said the Coalition had not contributed their fair share under the national land transport network agreement.

“There’s no reason why work can’t start on this now while we continue to negotiate with the Turnbull government to get Queensland’s fair share," he said.

"We just need Malcolm Turnbull to get the funding flowing now.

“This is a huge project which we know will take years to complete, so let’s get to work straight away and start to see this infrastructure delivered for the Sunshine Coast.”

LNP leader Deb Frecklington said the Sunshine Coast was finally getting what it deserved.

"Sunshine coast residents deserve a better deal. They deserve to have this duplication built, they deserve to get home sooner and get to work quicker," she said.

"These people have been waiting since 2009 when Labor first promised this and here we are in 2018 and we’ve got a hollow promise, because we now hear the Labor premier decided to not stump up the full amount of cash for their share."