Plaid Cymru’s general election chief Dafydd Wigley called yesterday for the 400,000 Welsh people living in England to vote Green in May.

Making an appeal to ex-pats 99 days before polling day, Baron Wigley said that both parties were committed to ending austerity, scrapping Trident and protecting the environment.

The former Plaid leader said their votes could help the joint Plaid, SNP and Green group hold the balance of power if Britain’s most unpredictable election ever ended in a hung parliament.

Speaking in the Lords, he said: “In the coming election, the three parties offer an alternative agenda to the stale, failed policies of the Tories and Labour alike.

“This is not a call for a formal election pact, as it would be arrogant for any politician to think that they can trade people’s votes.

“It is however a constructive suggestion to maximise the impact of the three parties in the new House of Commons.”

Plaid’s position was welcomed by Green leader Natalie Bennett, who said their parties’ Commons co-operation was “building a new model of politics that we need for the new age of multiparty politics in Britain.”

But she made it clear that the “fast growing,” semi-independent Wales Green Party would continue to contest elections against Plaid.

Labour candidate Calum Higgins pointed to the latest Welsh poll that put Plaid on just 10 per cent as proof that the election race was between Labour and the Tories.