Senior Green Party figures have described Reform as incredibly dangerous while outlining plans to strengthen their position across Sussex.

The party’s inaugural MP, former Brighton Pavilion representative Caroline Lucas, joined current leader Zack Polanski for a conversation with The Argus about the growing momentum behind their movement.

Following Mr Polanski’s appointment as leader in September, membership numbers have climbed dramatically, exceeding 200,000 by early March. The party has also attracted numerous high-profile switchers.

In February, the Greens hosted their largest event outside their annual conference at the Brighton Dome, recording an episode of Mr Polanski’s Bold Politics podcast featuring Ms Lucas as a panellist.

Ms Lucas achieved a landmark victory in 2010, having assumed leadership of the party two years earlier. She secured Brighton Pavilion from Labour with a margin of 1,252 votes and became the first woman to sit for Brighton in Parliament, serving for 13 years.

Shortly after the podcast recording, the party achieved another breakthrough in the Denton and Gorton by-election, with plumber Hannah Spencer elected as their fifth parliamentarian.

The party now anticipates winning more than a hundred constituencies at the next general election.

Among Sussex’s most significant recruits is former Labour MP for Brighton Kemptown Lloyd Russell-Moyle.

Mr Polanski declined to confirm whether Mr Russell-Moyle would contest his former constituency, which the party hopes will follow neighbouring Brighton Pavilion in returning a Green MP.

Mr Russell-Moyle informed The Argus of his intention to seek reselection for the seat he held between 2017 and 2024.

The Greens will choose candidates for the 2029 general election during summer 2026, with all selections determined through local party member ballots.

Candidate selection is entirely a matter for local members to decide, according to Mr Polanski.

He indicated the seat would definitely be a target at the next general election, with the party absolutely looking to expand and win additional Green MPs, with areas like Kemptown very much under consideration.

Ms Lucas dismissed the idea of limiting ambitions to Kemptown alone, expressing confidence in winning in Hove and declaring there was no ceiling to their aspirations. She noted the party was expanding at an extraordinary pace and attracting members from across the political spectrum, especially from Labour.

The Greens are eyeing gains in Hastings and Eastbourne, currently held by Labour’s Helena Dollimore and Liberal Democrat Josh Babarinde respectively.

Ms Lucas expressed belief that the party had entered uncharted territory warranting very considerable ambition.

She observed that many disenchanted voters were abandoning Labour, citing profound disappointment that the party had failed to deliver on its promises of change after gaining power. There was also genuine apprehension about Reform, she said, with many viewing a Green vote as the most effective means of countering that threat.

Ms Lucas characterised Reform as profoundly dangerous, warning they would dismantle decades of progress on rights, environmental protection and social justice. She acknowledged the genuine risk they posed, while suggesting some voters might be drawn to them as a protest against the entire political establishment. Her message to those considering Reform was that alternative methods existed to challenge the system without promoting hatred and division, noting that many people attracted to Reform did not actually align with their policies.

Reform leader Nigel Farage visited Sussex on Wednesday as part of local election campaigning.

Mr Polanski explained that his party’s approach to winning over Reform supporters involved direct engagement, going from door to door with a constructive vision for the future centred on reducing household costs, safeguarding the NHS and revitalising public services.

Water quality and sewage overflows represent major concerns for Sussex voters.

The Greens maintain that water provision should be returned to public ownership, with Mr Polanski arguing companies should receive no compensation in the event of renationalisation. He noted many water assets were essentially worthless and insisted water must be treated as a fundamental right. The renationalisation process should ensure bill payers bear no responsibility while shareholders and chief executives who had presided over deterioration of the system would face consequences for their failures. He expressed bewilderment at the notion that those who had driven water companies into the ground should subsequently be compensated for returning them to public hands.