The London mayor, Sadiq Khan, has said his team could go in this week to tackle the Southern rail strike if the government stopped “playing politics” and gave Transport for London (TfL) responsibility for commuter services.

Pleading with the government on behalf of commuters and London businesses, Khan said: “My message to the government is let my team go in. We can go in this week to help run this Southern line.”

Speaking on BBC Breakfast, he urged the transport secretary, Chris Grayling, to put party politics aside by giving a Labour mayor responsibility for Southern.

On Tuesday, Grayling dismissed the idea as “nonsense” and said in a letter to MPs: “Transport for London has no experience of running a mainline railway like this.”

But Khan said TfL had a better record than private operators. “Transport for London has fewer cancellations, fewer delays and fewer strikes. Since I became mayor, we have had 92% fewer strikes because I talk to those who represent our workers,” he told the BBC.

He also pointed out that Grayling’s predecessor, Patrick McLoughlin, and the former mayor of London Boris Johnson agreed in January that the government would hand over responsibility for running commuter trains on the Southern, Southeastern and South West Trains networks to TfL.

Khan said: “The previous government made a deal with the previous mayor. The only difference is I’m a Labour mayor. How is that fair on the commuters and businesses?

“Chris Grayling is playing party politics with commuters, with businesses and with London. I say stop it. We can do a deal with you, the government.”

He pointed out that last week, a letter from Grayling to Johnson had rejected the idea of transferring suburban lines to TfL, because the transport secretary did not want to see the services “in the clutches of [a] Labour mayor”.

Khan said: “We have got to do better than this. We have got to provide a system that is fair to commuters and hasn’t had the appalling service that commuters receive every day from Govia [Southern’s owner].”

He pointed out that Conservative-run councils, including Surrey, Hertfordshire and Kent, supported the idea of TfL taking over suburban services.

“We would make sure the longer lines carry on running under the franchise system, so the government can focus on the longer lines and let us look after the suburban lines. It’s a win win,” Khan said.

“Why the government says no is purely party politics. And in the meantime, we are losing tens of millions of pounds for our businesses, commuters are suffering and patients can’t make appointments. How is that right?”

Grayling was scathing about the suggestion in an interview with LBC. “He’s got some significant problems with Transport for London having big financial difficulties, the Piccadilly line is in a state of chaos, he’s running out of money for projects already in the pipeline and he’s making grand promises about things like bridges over the Thames he hasn’t got the money to build. So I’m afraid people should take what the mayor says with a pinch of salt,” he said.