While the world was distracted with the Iran deal, the large payments made to Michael Cohen’s shell company and a potential war in the Middle East, the White House quietly killed the funding for a key system to monitor greenhouse gas emissions around the globe.

First reported by Science on Thursday, "budget constraints" have forced NASA to end its $10 million-a-year Carbon Monitoring System (CMS), a vital resource for the agency to understand global carbon flows.

The tool is critical to monitoring countries’ greenhouse gas emission levels and to track whether they're meeting targets set out in the 2015 Paris climate accord.

Trump has already signaled his intent to withdraw from the Paris agreement, though the U.S. will remain part of the pact until its exit is formalized in 2020.

Trump has repeatedly threatened NASA's earth science budget and other climate missions, in favor of boosting the fossil fuel industry. The budget passed in March by Congress omitted any mention of CMS, effectively ruling out the use of carbon monitoring projects in the future.

NASA attempted to defend the decision Friday, saying it won’t have a major impact on its climate monitoring work.

**"**The winding down of this specific research programme does not curb NASA's ability or commitment to monitoring carbon and its effects on our changing planet,” Steve Cole, a NASA spokesman, told the BBC.

Climate scientists disagree.

“If you cannot measure emissions reductions, you cannot be confident that countries are adhering to the agreement," Kelly Sims Gallagher, director of Tufts University's Center for International Environment and Resource Policy, told Science, adding that canceling the CMS “is a grave mistake.”

Jon Foley, an environmental scientist and director of the California Academy of Sciences, called the move “a surgical strike against climate science and monitoring reductions in greenhouse gas emissions.”

Ever since concerns over climate change were first voiced in the ‘90s, regulators have struggled to find accurate ways to measure carbon emissions. Most countries publish estimates based on the amount of fuel used in transport, energy and industry — but these can be wildly inaccurate and easy to fake.

Space and aircraft-based systems such as CMS are seen as a better way to hold countries accountable.

News about the CMS cancellation came while climate officials from around the world gather in Germany to hammer out a rulebook for how to implement the landmark Paris accord.

Yet despite weeks of talks, the officials have yet to come to an agreement. “We have been here for two weeks and fell short of what was foreseen,” Elina Bardram, the European Union's top climate negotiator, told AFP. “We were not even close.”