For the first time that any of us at Positive Money can remember, a major UK political party will fight a general election on a commitment to take control of the money supply away from private banks. The Green Party manifesto pledges that “the creation of money should become the function of a new monetary authority, independent of day-to-day government control”.

It is an important milestone for Positive Money’s 25 000 supporters, who are helping to make money creation a matter of mainstream political debate.

The potential significance of the Greens’ manifesto pledge is compounded by the fact that the 2015 election is expected to be one of the closest elections in decades. Ed Miliband’s chances of taking office are likely to depend on support from more than one of the smaller parties, and even just one or two Green MPs could hold significant sway over a minority government. Natalie Bennett has ruled out backing the Conservatives.

The test of the Greens’ commitment to monetary reform will be what role it takes in their post-election negotiations. Caroline Lucas has said that the Greens would support a minority Labour government on a “case by case” basis, and proposals for an in-depth review of money and credit in our economy could become a key potential concession for her and her colleagues to extract. In fact, Labour MPs have already voiced their support for a Parliamentary Commission on Money and Credit in a backbench debate last year.

We’ll be working with any newly elected Green MPs to help them champion monetary reform in Parliament, and Positive Money supporters will hold them to account on their manifesto pledge.

In the meantime, you can sign our petition here telling the next Prime Minister that money creation should only be used in the public interest. We’ll be delivering it to Number 10 shortly after the election.