Sir Ed Davey has said the EU is a 'long-term thing' but is not currently on the table - as Liberal Democrat tensions grow over Brexit.
He added that he has worked very carefully with the foreign affairs spokesman Layla Moran to make sure that we can improve our relationship with Europe.
But he added that at the moment those sorts of things are not on the table.
Questions remain over the party's stance on Brexit, with Sir Ed heckling on Sunday after insisting to delegates during a Q&A session that he was 'campaigning hard on Europe'.
Sir Ed has said people on the doorstep aren't talking about Europe, but senior figures - including former leader Sir Vince Cable - have argued the party should not lose sight of the issue.
An ultimate goal to return to membership in the bloc is currently official policy, but the president has been reluctant to speak publicly about this and says it is currently off the table.
Jo Swinson, a former Lib Dem leader, ran the party's worst campaign in 2019 - a promise to revoke Brexit without a referendum, but ended up losing her seat.
Sir Ed has advocated 'root-and-branch' reform of the existing trade and co-operation agreement, but framed it as a long-term challenge, arguing that a'realistic' approach is necessary.
The party has scrapped a longstanding pledge to put a penny on income tax to fund spending on the NHS and social care.
The Lib Dems have called for the increase since 1992 but have scrapped it in a bid to pile pressure on Tory MPs in the so-called blue wall of safe southern seats.
Sir Ed said: The commitment was unsustainable when people are struggling with the cost-of-living crisis.
He added: 'It's been two years of frozen income tax allowances and four more years to come. In those six years of stealth income tax rises, that amount to more than a 3p rise in the basic rate of tax.
t asks working families to pay more in taxes. Sir Ed, however, said the party would hike levies on banks and large companies.
Reversing cuts to the surcharge on the financial sector and increasing the burden on water, oil and gas firms would help to finance the party's newly adopted multibillion-pound policy platform, he said.
It adopted an early version of its manifesto at its annual conference on Sunday, with policies aimed at winning over voters in Tory heartlands.
It will lay out a fully costed document in November next year, which is expected to be released in the next general election next year.
Among its policies is a £5 billion social care pledge, which would see individuals 'be looked after where they want to be at home' and improved GP and mental health services.
Sir Ed has argued that the social care package would be able to pay for itself by saving £3 billion other than the NHS, e.g. by freeing hospital beds and relieving pressure on care homes.
Newly relaxed housing targets may also prove controversial with activists when they are debated on Monday.
The party has vowed to build 150,000 social homes a year - changing from a pledge to build 380,000 homes annually in its 2019 manifesto.
But one Lib Dem council leader, speaking at a fringe event alongside housing spokeswoman Helen Morgan, said abandoned national housing goals would be an 'abdication of responsibility' and warned against 'fluffy local targets'.