The Greens face ruin if the Government fails to steer the bill on PR through Westminster in time for next year's European elections. The party has staked most of its budget on gaining its first seats in the European Parliament elections in June, but knows that PR is essential if it is to enjoy an electoral breakthrough.
The Greens stand to lose almost all of their savings - and gain no MEPs - if the Government is unable to persuade the House of Lords to get the bill on PR through Parliament. Staff at Green Party headquarters, hired to bolster the European campaign, fear the sack.
"The Green Party has basically committed everything it has to the Europe campaign," said Kevin Saunders, a party spokesman. "The money is being spent as it comes in. This is seen as a make-or-break campaign for the Green Party. It is the first time we have a chance of being elected on a nation-wide vote."
The party - whose membership has shrunk to 5,000 from a peak of 20,000 - has been saving for years to fund the campaign. They face losing more than pounds 160,000 if the Government is forced to return to the old first-past- the-post voting system, which will make it impossible for the Green Party to gain seats. It has already invested pounds 55,000 for candidates' deposits, pounds 87,000 for new Euro-election staff and pounds 20,000 for a TV election broadcast.
This month the Green Party issued an appeal to Jack Straw, the Home Secretary, and the Lords to stop playing "ping pong" with the Bill introducing PR lists at the Euro-elections. The Greens could gain between three and six seats if enough voters mark the Green Party as their first, second and third choices on their ballot papers because, under PR, votes are redistributed. In London the Green Party needs only 9 per cent of the vote to win one seat and in the south-east 8 per cent.
The party's membership peaked after its 15 per cent showing in the Euro- elections of 1990. It has since been plagued by internal rows between radical "dark greens" and moderate "light greens". It is hoping to capitalise next year on the growing interest in environmental issues and to attract former Labour voters disaffected by "control freakery".
The Greens, buoyed by the success of their German counterparts in this year's general election, were the first to select candidates for the 1999 European poll. The party is opposed to the single European currency and global free trade. It wants to decriminalise marijuana use and investigate the plant's therapeutic properties and to ban genetically modified food and crops, road-building and nuclear power.