The marshals, who reportedly could earn salaries of up to £30,000, are being created to help enforce the tightened social distancing rules.
Grant Shapps said they would remind people to wear face masks in shops and look out for groups larger than six people gathering.
Transport Secretary Grant Shapps has defended the new Covid marshals after Prime Minister Boris Johnson announced the idea as the UK tackles a sharp rise in coronavirus cases
From Monday, people are banned from gathering in groups larger than six outdoors or indoors, with a limited number of exemptions.
Street wardens would be the “ideal” candidates to create the army of new “Covid marshals”, the Transport Secretary has claimed.
They will be given local authority high visibility uniforms, badges, and clipboards so the public are aware of who they are.
Welwyn Hatfield MP Shapps said street wardens, who already patrol neighbourhoods to support the police, could carry out the role.
But the idea has been widely mocked, with critics deriding them as sounding like the “worst sort of busybodies”.
Prime Minister Boris Johnson said the marshals will support councils to “help ensure social distancing in town and city centres” to stop the spread of coronavirus, along with environmental health officers.
Defending the policy, he said: “People actually genuinely just want to do the right thing.
“In my area, we have people called street wardens who are marshals on the street.
“They typically look after the neighbourhood particularly in the town centres and that sort of thing.”
Describing what they would do, the Tory MP said: “Just to remind people – face mask on if they’re going into shops, to look out for groups of people.
He went on: “They would be ideal people to be marshals employed by the council.”
“Anyone breaking it could be dispersed, they could be fined, and possibly arrested.
“This is not going back into a full lockdown.”