A group of senior Liberal Democrats has warned that the party under Ed Davey is being too cautious and needs to properly explain to voters what it actually stands for before the general election. In a rare expression of open dissent within the Lib Dems, 30 senior members, including a Lords frontbencher and eight members of the party’s policy committee, said there was a need to be bolder in areas including Brexit, human rights and the environment. With Rishi Sunak’s government losing impetus and Keir Starmer’s Labour party being ultra-careful, “there is a massive opportunity for a liberal alternative based on internationalism, environmental awareness and modernising Britain”, they said in a joint letter to the Guardian. “But we believe the Liberal Democrats are swerving this opportunity, not seizing it,” said the signatories, who include Sarah Ludford, the Lib Dem peer who speaks for the party on Brexit, who signed the letter in her personal capacity. “It is crucial that we are brave and honest about the challenges a new government will face, with distinctive positions the Tories would never take and Labour dares not adopt.” One signatory said the letter was not intended as a direct attack on Davey who, despite a string of dramatic byelection successes as Lib Dem leader, was overseeing a party still mired at about 10% or 11% nationally in the polls. Instead, they said, there was concern that the team around Davey was focusing too narrowly on efforts to win seats by attracting disgruntled Conservative voters, and was shutting down any efforts to be more forthright on policy. “We’re not criticising the target seats strategy, but focusing on target seats alone is not enough,” said Duncan Brack, a member of the party’s federal policy committee who was an adviser to Chris Huhne in the coalition government. “We need to stand for something inspiring. Otherwise, why should people join the Lib Dems, pay money into campaign war chests, go delivering and canvassing? And why should anti-Tory voters vote for us as opposed to another opposition party if it’s not clear what we stand for?” The letter said that with Starmer refusing to engage on Brexit, the Lib Dems could argue for rejoining the EU’s single market, and express more loudly the party’s “bolder policies than Labour on the environment, fair votes and human rights”. It added: “At a general election, echoing Labour’s general antipathy to the Tories through local campaigns is part of the battle but insufficient on its own.” Such an approach, it said, helped Paddy Ashdown win 46 seats for the Lib Dems in the 1997 general election. “He set out a clear alternative to both big parties,” the letter said. “With Labour in the ascendant again, today’s Liberal Democrats must heed his success.” Other signatories include local party chairs, former chiefs of staff to two previous leaders, and former MPs, with the organisers saying a number of other senior Lib Dems, including serving MPs, backed the idea but did not want to be publicly disloyal. A Lib Dem spokesperson said: “It would be a comforting luxury to act as the most democratic thinktank in British politics and navel-gaze amongst ourselves. But after this Conservative government has wrecked our economy, broken our NHS and damaged Britain’s reputation on the international stage – the focus of this party is to defeat as many Conservatives as we can at the next election, and get them out of power.”