Walker has been tasked with developing and delivering a comms and media strategy for the Party, including plans to reach new audiences and increase the impact of its campaign messaging.
"I'll be working to make the Greens more visible and [contributing] to campaign and election planning for whenever the next general election may be, and beyond to local and mayoral elections next year," Walker told PRWeek.
She will lead a team of six at the Party’s London headquarters and will report to its chief executive, Mary Clegg.
Walker began her career as a broadcast radio journalist before working for the International Transport Workers’ Federation, a global assembly of transport unions.
During nearly seven years with the organisation, Walker was a campaign comms specialist, rising to become its acting head of campaign comms.
She went on to co-found CORA Communications, which specialises in social-change campaigns, with Isabel Cortes.
Walker said she would still retain some involvement in the firm, despite her new role.
Commenting on why she decided to work for a political party for the first time, Walker said she wanted to help the Greens push back against austerity, the creation of the hostile environment and "corporate greed which ignores people and planet".
She added: "I genuinely believe we're at a pivotal moment in UK politics… I want to use my skills and experience to help get more Greens elected. We're in the middle of a Green Wave and we need to maximise on that increased awareness and turn it into success at the polls. It's a really exciting time to be involved."
The political environment
With the Brexit process in turmoil this week, following MPs' refusal to allow the Government's EU Withdrawal Bill to be rushed through the Commons in three days, a general election is widely considered to be likely either side of Christmas.
Issues around climate change have risen to greater prominence in the minds of the public than ever before this year.
The emergence of teenage climate protester Greta Thunberg has inspired millions of children and adults around the world with her school climate strike, as well as castigating world leaders for their environmental record at the United Nations last month.
Meanwhile, Extinction Rebellion's sustained protests have also driven climate change up the agenda and achieved widespread media coverage, although not always positive.
Walker said of the backdrop to the forthcoming election: "I'm hoping to make a significant contribution to getting more Green politicians into power through increasing our reach and visibility and pushing home the message that protecting our environment feeds into every other aspect of our lives."
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