Keir Starmer’s team is being urged to refute any Conservative claims that Labour will be propped up in government by the SNP after the next general election, by drawing up early and clear “red lines” against any deals with the Scottish party. A number of senior figures from Labour’s 2015 election campaign – during which the Conservatives repeatedly claimed that Ed Miliband, the party leader at the time, would be dependent on the SNP – are urging their leadership to neutralise this tactic well before the next election. Some want the party to rule out any Scottish referendum during the next parliament, or extra funding in return for SNP support. Labour’s current position is that no deals will be made either before or after the election, but officials are already considering how they could do more to counter attacks by the Conservatives based on a potential relationship with the SNP. Miliband’s 2015 team said the Tories “ambushed” them with claims about a deal after opinion polls predicted spectacular gains by the SNP. A poster showed Miliband in the pocket of then SNP leader Alex Salmond. The Labour team said they were horrified at they way the threat was influencing voters in their own focus groups. Several told the Observer that the party should act now to counter that threat, well ahead of the chaotic environment of a general election campaign. Douglas Alexander, who was chair of general election strategy in 2015 and lost his seat to the SNP, was among those to call for early action. “There is no economic coalition that the Conservatives can put together across the UK that makes any sense in time for the next general election,” he said. “So they will try to create a cultural coalition instead. A central part of that will probably be yet more appeals to English nationalism. Labour is in a stronger place to set out its position in relation to the SNP than it was in 2015. The SNP have long lost the momentum they enjoyed in the months following the 2014 independence referendum. “My own instinct is that Labour can deal with the issue early by saying clearly in Scotland and across Britain that the way to get a Labour government is straightforward … vote for a Labour MP. “It is perfectly possible to say, ‘The only coalition we are seeking is one with the voters. Labour will seek to deliver its manifesto and other parties will need to make their choice about whether to support us.’ Getting that clarity on the record works both as a campaign message and as a strategy for governing.” Other senior figures from Labour’s 2015 campaign think the party should go further. They said Miliband’s eventual declaration that there would be no deals was “dragged out of us” after initial attempts to bat away the issue. “I would try to put in clear red lines well ahead of an election,” one said. “They should rule out a coalition. They should rule out a second independence referendum. The other obvious area to go is ruling out additional money for Scotland outside of the settled balance of resources within the UK. That would make quite a difference.” Some believe that while Labour should consider its response to this line of attack, the claim will simply not be as effective against Starmer’s party. The Labour leader is already competing with Boris Johnson in terms of who people prefer as prime minister – something Miliband never managed to achieve – and advisers do not think that Starmer is perceived as weak in the same way. Some pollsters also believe the whole idea that the issue sank Miliband’s bid for No 10 is overblown, because in reality, polls had overstated Labour’s support throughout the campaign. Current polling does not suggest major voter concern. An Opinium poll for the Observer earlier this month found that, when given a hypothetical choice, 46% would prefer a minority Labour government led by Starmer with support from the SNP and the Lib Dems, while just 32% would prefer a Tory government led by Johnson. Meanwhile, 45% would prefer a Labour and Lib Dem coalition headed by the party leaders Starmer and Ed Davey, compared with 35% who would rather see a Tory government led by Johnson. Members of Labour’s 2015 team who spoke to the Observer agreed that Starmer should make an early intervention. One suggested that as an alternative to ruling out all deals with the SNP, Labour could include the party in a commission examining what an independent Scotland would look like, alongside a package of further devolution. “If an overall majority looks unlikely, we will be asking people to vote for a minority government living day-by-day and by the seat of its pants,” they said. “It’s a recipe for instability and another election, which won’t be a popular prospect. “The alternative is to say that everyone knows there is going to be another referendum at some point and the right way to proceed is to determine what the options to put to the people would be in detail, rather than have a vote about abstract concepts. On that basis, we might be able to say a confidence and supply motion like the one we had with the Liberals in the 1970s is possible. There would be no SNP ministers, and no special favours either above or under the counter.” Among Starmer’s team, several believe any Tory attack focusing on a “coalition of chaos” headed by Labour is undermined by Johnson’s chaotic leadership, the Tory deal with the DUP in 2017 and the fact that the SNP’s place in British politics is less newsworthy than in 2015. In fact, some are more worried about a Tory suggestion that Labour’s left will end up wielding influence over Starmer.