The vast majority of carbon emission reduction pledges countries made under the 2015 Paris accord aren’t nearly enough to keep global warming in check, a new report has warned.

The study, called "The truth behind the climate pledges" and published by the nonprofit Universal Ecological Fund, ranks nearly three-quarters of national pledges as "insufficient", including those of major polluters such as China, the United States, and India.

A dozen pledges were judged only partially sufficient, and just under 20 percent were deemed ambitious enough — most of them in the European Union.

The US withdrawal from the pact is going to make the deal's targets even more difficult to reach, one of the authors' reports, Sir Robert Watson, told Euronews.

'A terrible signal'

"As one of historically the largest emitters in the world, and currently one of the highest per-capita emitters, it sends a terrible signal to other countries that the US is not committed to addressing the climate issue," said Watson, former chair of the Intergovernmental Panel on Climate Change as well as a former White House Senior adviser.

French President Emmanuel Macron and his Chinese counterpart Xi Jinping signed a joint statement on Wednesday reaffirming their support for the Paris agreement, calling it an "irreversible" process.

To achieve the Paris 2015 climate accord's most ambitious goal of keeping global warming below 1.5°C above pre-industrial levels, global greenhouse gas emissions would need to be reduced by 50 percent by 2030.

China, the United States, the European Union and India account for around 60 percent of the world's CO2 emissions, so any action on their part is key to reaching the Paris targets.

China has an ambitious pledge on paper, but it's not enough in practice, according to this new report.

"While the emissions intensity targets of China and India are very good, their economic growth is so strong that their emissions will increase between now and 2030," Watson predicted.

Europe in the lead

The EU has a binding target to reduce greenhouse gas emissions by 40 percent below their 1990 level by 2030.

European countries are "clearly in the lead," said Watson, calling the bloc's pledge for 2030 "very encouraging".

"Obviously we need even more from the EU, and by 2050 we need the EU to be carbon neutral," he added.

EU member states are currently considering asking the European Investment Bank to stop funding fossil fuel projects, in what could be a breakthrough in the bloc's climate policy.

"Anything that helps move us away from fossil fuels is a step in the right direction," said Watson.

You can watch the full interview on Euronews Now by clicking in the player above.