The Green Party plans to splurge more money on international aid than is currently being spent on defending the UK in plans branded a 'complete fantasy' by rival parties.

Amid warnings this week Britain is 'underprepared' for war, the Greens want to spend 2.5 per cent of national income on supporting developing nations by 2030 – more than the UK's current defence budget.

This comes as Green leader Zack Polanski told the Daily Mail he backs an 'alternative' review into UK defence which focusses on threats to the climate.

With Britain's enemies circling, Labour last year slashed the UK's overseas development assistance (ODA) budget to 0.3 per cent of national income to be able to boost military spending to 2.5 per cent by 2027.

But in a policy document seen by this paper, the Greens would devote one per cent of national income to ODA, and 1.5 per cent to climate finance – which helps nations cut their emissions and cope with climate change.

The paper explains that ODA and climate finance 'need to provide for planet repairs (climate debt) and reparations for colonial exploitations, enslavement and trafficking of people over the past few centuries'.

It adds: 'Value has been, and continues to be, extracted from the global south through unequal trading rules and practices.

'Colonialism and the fossil fuel era reconfigured the world economy in a way that has harmed many countries in the global south.'

The Green Party would also demand foreign aid be given to less wealthy countries in the form of grants not loans – meaning the UK would never see the money returned.

And the Greens also intend to write off all international debt from least developed countries and those which need support in reaching development targets.

The policy says the British Government should take 'a strong international lead' in pursuing this goal with the help of international partners.

It adds: 'The rich countries should agree to write off the annual transfer of wealth which goes from the developing countries to the North each year.'

But shadow foreign secretary Dame Priti Patel yesterday branded the Greens' plans a 'complete fantasy'.

She said: 'At a time of global conflict twinned with pressure on the public finances, it's ludicrous that the Greens are prioritising foreign aid over defence spending.

'The first duty of any Government is to keep the public safe – the British public, not foreign publics. Compared to that, foreign aid should be well down the list of priorities.'

This comes as Lord Robertson, an author of the Government's Strategic Defence Review (SDR) and Labour peer, this week blasted Keir Starmer for prioritising welfare spending over defence – saying that Britain is 'underprepared', 'underinsured' and 'under attack'.

But Mr Polanski said 'the first place' he would focus in reviewing UK defence is our vulnerability to climate change and other 'emerging threats' – and called for an 'alternative' SDR.

'I think ultimately it needs to be looking much more holistically at other emerging threats such as cybersecurity, pandemic resilience and tackling the climate crisis,' he said.

The Green leader also took issue with the 'arbitrary' nature of defining defence spend as a percentage of national income – saying 'once we know exactly what it is that we need to spend money on, then I think that's when you decide how much you want to spend'.

Mr Polanski said he has not yet consulted defence officials on these plans.

A Green Party spokesperson said: 'Our International Policy chapter was last amended in October 2025. However, Greens have made numerous interventions on international issues in recent months.

'For example, Green MPs and peers wrote to Keir Starmer demanding answers to a series of questions and an end to British involvement in the illegal US/Israeli war on Iran.

'There's a difference between documents outlining broad values and priorities, and interventions on rapidly evolving situations.'