Carrie Harper

Carrie Harper is a Plaid Cymru spokesperson who became a public figure in the 2026 Welsh Senedd election campaign when she warned in April 2026 that Green Party votes could enable Reform UK gains in Welsh constituencies. Her warning came after a Wales Green candidate described Plaid as "not a left-wing party" and Green leader Anthony Slaughter called the Greens the "only left-wing party in Wales".

The public exchange between Plaid and the Wales Greens reflects a central tension in the Welsh election under the new 96-seat closed-list PR system. Under the new system, in which voters choose a party rather than a candidate across 16 six-member constituencies, each percentage point of vote share affects list seat allocations. YouGov's Senedd MRP projects Plaid Cymru on 43 seats and the Wales Greens on 10, with a combined 53 giving a notional Plaid-Green Coalition four seats above the 49-seat majority threshold. Both parties recognise that fragmentation between them could give Reform more seats than the projections suggest. Harper's warning targets voters who might prefer the Greens but fear that tactical fragmentation advantages Reform.

The public disagreement is being conducted three weeks before a vote is cast under a closed-list PR system that Welsh voters are using for the first time.