Green Party conference backed detailed policy that will see the party press the new government for much closer relations with the European Union.
Green MP Ellie Chowns said: “The conference has made it very clear that people and planet would benefit from much closer relationships between our country and the European Union.
“We will be pressing the new government to be braver and bolder in overcoming the negative impacts of Brexit.
“Full membership of the EU remains the best option for the UK, and we are in favour of pursuing a policy to re-join as soon as the political will is present.
“Of course, that means building the widespread public support we need before a decision to rejoin is made.
“There are win-win first steps that the new government should be taking today. For instance, working with the EU to tackle the twin crises of climate breakdown and biodiversity loss would deliver the change we need and create public confidence.
“We should also rejoin the Customs Union to begin to overcome the obstacles that small businesses have faced in trading with our closest partners since Brexit.
“While joining the Single Market would provide benefits in terms of free movement of people, goods, services and capital, membership of the Single Market without membership of the EU would not be an ideal long-term solution because the UK would not be a full partner in decision making processes.
“We’ve learned from the divisiveness of Brexit that binary choices push people apart rather than bring people together.
“So, we are proposing the use of citizens’ assemblies to support the wider public to make well-informed decisions about complicated political issues such as our future membership of the EU.”