The Green party plans to focus as many resources as possible on four potentially winnable seats at the next general election, and would be open to doing a deal with Labour if needed, the party’s co-leaders have said at the start of their conference. After a joint speech in Brighton, where they accused the government of “playing cynical political games” with the climate emergency, Carla Denyer and Adrian Ramsay told the Guardian that the party hoped to exercise influence beyond its size and funding. With a base of activists massively increased since 2019 amid a subsequent quadrupling of councillors, the Greens in England and Wales hope to replicate the intense targeting that helped them win the Brighton Pavilion seat in 2010. Denyer told the Guardian the party would be “laser-focused on those four target constituencies” – Brighton Pavilion; the newly created seat of Bristol Central, where Denyer is standing; Waveney Valley, another new seat across parts of Norfolk and Suffolk, where Ramsay is standing; and North Herefordshire, where Ellie Chowns is standing. Emphasising the point, Chowns and Siân Berry, who is hoping to succeed Caroline Lucas in Brighton, joined the co-leaders on stage after their speech. While a tally of four is ambitious, with some psephologists saying the party could do well even to hold the Brighton seat, the aim is to hold disproportionate sway in parliament, especially if Labour falls short of a majority. A Green group of MPs would be open to some sort of post-election deal with Labour, Denyer said: “We’ve always been really clear that we’re happy to work with other parties in areas where we agree, which is what Greens do all over the world. “Labour are not emitting very collaborative noises at the moment, but we have continued to be clear that our door is open and if Labour are in a position where they have the opportunity to form a government but don’t have enough seats on their own, then we will definitely be open to having conversations with them. But we wouldn’t just be sort of rolling over and doing what they say.” The three-day conference, likely to be the last before an election next year, is intended to put across a disciplined and focused message to voters, and to inspire members to commit time and effort to campaigning. While Denyer’s target Bristol seat mirrors the type of urban demographic with which the party found success in Brighton, recent local election wins in rural areas have boosted hopes for fights such as Ramsay’s, in a brand new constituency where so far he is the only declared candidate. Unveiling a policy platform including a pledge for tenants to be able to force landlords to properly insulate their homes, the co-leaders’ speech saw them also attack Labour, with a charge that the party under Keir Starmer has become so timid it is a “bystander to the Conservatives’ chaos”. “No matter what new climate crime or damaging policy the government comes up with, Labour somehow manages to disappoint us just as much,” Ramsay said. “Time after time, they come out swinging at the Conservatives, and then when asked: ‘Does that mean you’ll reverse these decisions if you make it into government?’ – radio silence.” Denyer used her sections of the speech to accuse the Conservatives of “doubling down on their climate vandalism”, and also of “falsely pitting the cost of living against the cost of net zero”. The pair also castigated Labour for abandoning poorer voters by ruling out any form of tax on wealth, thus limiting its fiscal choices. “They’re turning their backs on the voters who so desperately need them to rise to the scale of the challenge,” Ramsay said. “They claim to have done this in the name of fiscal responsibility. But what’s responsible about letting 250,000 children grow up in poverty by keeping the Tories’ cruel two-child benefit cap?”