The Green Party is preparing to field 500 candidates in next May's general election as it aims to capitalise on the Lib Dems' unpopularity and become Labour's main challengers on the centre-left.

Party membership has almost doubled to more than 25,000 since January and it is planning to target 12 key seats next year.

Here's where they stand on key issues...

Employment

“Green new deal” to create one million jobs in renewable energy, insulation, social housing, public transport and waste management.

Taxes

Wealth tax of up to 2 per cent on the assets of 300,000 people who are worth more than £3m, the country’s richest 1 per cent.

Wages

National minimum wage to be lifted to living-wage levels and to reach £10 an hour by 2020.

Pensions

End pensioner poverty by introducing a weekly “citizen’s pension” of £170 for a single person and £300 for a couple.

Energy

Targets and timetables for improving efficiency and reducing greenhouse-gas emissions across all sectors of economy. Party wants electricity use to be reduced by one-third by 2020, by a half by 2030, and by two-thirds by 2050.

Health

Accuses Labour and Tory governments of introducing privatisation by stealth into the National Health Service. Pledges to “maintain a publicly funded, publicly provided health service”.

Railways