Ed Miliband will promise today that if a Labour government is elected in May it will put a home rule bill for Scotland before parliament in its first 100 days.

The draft clauses of a proposed parliamentary bill implementing the findings of the cross-party Smith commission on the devolution of further powers to Scotland were launched by Prime Minister David Cameron in Edinburgh last week.

In his first visit to Scotland since Jim Murphy was elected Scottish Labour leader, Miliband will also promise to immediately devolve control over the work programme jobs scheme to Holyrood if elected, a move which Labour still hopes to fast-track before the general election despite Conservative opposition.

Speaking before a campaigning visit to Glasgow with Murphy, Miliband said: “Just as in 1997, devolution will be one of the first things on our agenda for the next Labour government.

“We will put the home rule bill before parliament in the first 100 days of the next Labour government. This bill will give Scotland the powers that were promised over jobs, welfare and tax.

But we want to go faster. Scotland needs the job-creating powers that the Smith agreement promised. And Scotland needs them now. Next month, Labour will force a vote on our bill to pass these powers now. If that’s not accepted, we will devolve control over the work programme immediately on taking power, so Scotland has the tools it needs to put people back to work.

Praising Murphy, Miliband added: “Jim Murphy is already leading the agenda in Scotland. He’s getting to grips with the problems in Scotland’s NHS with his plan for 1,000 new nurses. He has set out a plan to deal with damaging job losses in the oil and gas sector. And he’s talking about how Labour will use the new powers to deal with unemployment and get our young people back to work.

“This will be real home rule for Scotland in the 21st century, giving Scotland the powers it needs.”

The Scottish National party dismissed the pledge as ‘laughable’. Deputy leader Stewart Hosie said: “The reality is that, with 70% of taxation and 85% of welfare spending staying under Westminster control, Labour and the other UK parties are offering Westminster rule not home rule – and it is embarrassing for Mr Miliband to try to pretend otherwise.”

Writing for the Guardian in response to the publication of the draft clauses last week, the SNP leader and first minister, Nicola Sturgeon, said David Cameron, who confirmed that the legislation would be in a Conservative government’s first Queen’s speech, had failed to deliver on the vow of substantially more powers to Scotland made by the three main Westminster party leaders in the final days of the referendum campaign.

Recent polls point to the size of the challenge currently faced by the Labour party in Scotland, suggesting that the SNP will gain an unprecedented number of seats in May’s general election, mainly at the expense of Labour.

The poll for Ipsos Mori last week gave the SNP a 28-point lead over Labour in Westminster voting intention, projecting 55 seats in Scotland for the nationalists and four for Labour. YouGov polling last November also revealed that Miliband’s approval rating in Scotland was even lower than in England, standing at -65.