Voters recognise that the next Westminster poll must be a “climate election”, the co-leader of the Scottish Greens has said.

Patrick Harvie said he is confident the Greens will win more than one seat in the election expected this year as people realise the importance of climate-related issues.

He told BBC Radio Scotland that north of the border, his party is aiming to stand “more candidates than ever before in more parts of Scotland than ever before”.

He said a decision on which seats to contest will be one for local branches, but the whole party shares the goal of standing in as many as possible.

Asked whether the Westminster election is something of a waste of time for the Scottish Greens in terms of how well they might do, Mr Harvie said it is actually “hugely important”.

It’s when Green votes are in the ballot box and Green voices are in the room, that’s when climate starts to matter to the other parties

He said: “Some of the biggest issues that are holding back Scotland in terms of things like climate progress and a more equal society are decisions that are made at Westminster, as well of course as the really relentless attacks that we are now seeing from a UK Government against the powers and the autonomy of the Scottish Parliament and the Scottish Government in a way that really goes against the vote to create the devolution framework in the first place.

“That absolutely adds to the pressure and needs to be challenged, and every Green vote in the ballot box adds to the pressure on other parties regardless of the number of seats.

“I’m actually confident that there will be more than just the one (MP). Caroline Lucas has been a fantastic green voice at Westminster as the only Green MP, representing Brighton Pavilion, but I’m actually confident that there will be more than one in the new session of Parliament.

“But regardless of where those seats are, Green votes in the ballot box will force the other parties to take notice.

“It’s when that happens, it’s when Green votes are in the ballot box and Green voices are in the room, that’s when climate starts to matter to the other parties.

“I think increasingly across the country, both Scotland and the rest of the UK, there are increasing numbers of voters who recognise that in the wake of an astonishingly record-breaking year in terms of the climate impact that we’re having, this has to be a climate election.”

Prime Minister Rishi Sunak has said he is working towards a general election in the second half of this year.

Mr Harvie also spoke about the Bute House Agreement, which sees the SNP and Scottish Greens work together in the Scottish Government.

He said as part of the Scottish Government, his party is able to “get in the mix of every part of the Government’s programme and bring Green influence to bear”.

He was asked if there is an argument that the Bute House Agreement is not necessary because there is no independence referendum on the horizon, and whether the Greens would be better supporting the SNP on things they agree with, but challenging them on areas of disagreement – as they were able to do before entering Government.

Mr Harvie, who is a Scottish Government minister under the Bute House deal, said: “The agreement did not create a pro-independence majority, there already was one, as there had been in the last session of Parliament.

“Our party the Scottish Green Party is a pro-independence party, it always has been as far as I can remember back to its inception, that’s not going to change.

“But the Bute House Agreement creates the opportunity for a solid policy programme that allows us to push the Scottish Government sometimes out of its comfort zone, that’s what we’ve always done.

“It’s very consistent with our approach which is to be constructive and challenging, not to demand the impossible but to show how things can be done for the better.”