Sunday train services will be as reliable as weekday services under plans to renationalize the railways, the new transport secretary will claim in his keynote speech on Monday.

Heidi Alexander has released a series of pledges on which the government will be judged by millions of passengers and its political rivals, saying she would build a network "where Sunday services are as reliable as Monday services". One of her top priorities.

Speaking on rail issues for the first time since taking over from Louise Haigh, who resigned in November, Alexander will set out the scale of the task ahead.

She said the new public body Great Britain Railways (GBR), to be established by legislation later this year, would be "second only to the NHS in size and importance".

The GBR is expected to employ around 90,000 people in total, while the NHS in England employs around 1.5 million staff.

As the private operator's franchise expires, the rail organization will manage the process of bringing the network into state ownership and will establish the operation of trains and tracks under the same agency.

Rail experts will express doubts about the government's chances of creating Sunday services on par with weekdays without first taking on powerful rail unions, who are likely to resist more Sunday work.

Just before last year's general election, rail industry leaders urged ministers to address poor Sunday services caused by staff shortages as many services were severely depleted.

State-run Northern Trains was particularly badly affected last summer, with 282 trains canceled on its network on one Sunday in late June.

Some operators reported that they were unable to operate as normal schedules due to staffing issues.

Former rail minister Norman Baker said delivering on the promise would be difficult because the union agreement did not require train drivers to work on Sundays.

“These agreements will either have to be renegotiated or drivers will have to be paid huge extra fees to come to work on Sundays.”

Baker said the entire process of setting up a network run by private operators has contributed to an overall shortage of drivers.

Mick Lynch, general secretary of the Rail, Maritime and Transport Union (RMT), said he was willing to discuss changes but the conditions were strict.

"We are prepared to work with companies and the Department for Transport to shape the future of our railways," he said. "This includes ensuring rail workers have a fair deal, prioritizing safety, health and work-life balance, as well as fair pay and conditions."

Alexander will say the aim of the reforms is to transform the railways from a "private profit" system to a "public benefit" operating system.

She will stress that renationalizing services will help deliver economic growth and local mayors will be given greater powers to tailor regional services to the needs of local people.

Ministers also promised that passengers traveling in England will see on screens at stations how often their trains are delayed and cancelled.