Big oil companies are spending millions to portray themselves as taking action on climate change, but their investments and lobbying activities don't live up to their planet-friendly claims, according to a new report.

An analysis from London-based energy and climate think-tank InfluenceMap found that the amount of climate-positive messaging used by five major oil and gas companies -- BP, Chevron, ExxonMobil, Shell, and TotalEnergies -- is inconsistent with their spending on low-carbon activities.

The report comes as scientists have grown increasingly urgent in their warning that the world must slash the use of fossil fuels to prevent catastrophic consequences of the climate crisis. It also comes amid fresh criticism of oil companies' growing profits as consumer energy costs soar.

The think tank analyzed 3,421 items of public communications materials for 2021 across the five companies and found that 60% of their messaging contained at least one "green" claim.

InfluenceMap then calculated the amount of money the energy companies expected to spend on green investments last year and found on average just 12% of their capital expenditure budgets were going toward what the companies themselves consider low-carbon or renewable activities.

In some cases, those figures are on the rise. Shell, for example, says it plans to spend 12% of its capital expenses on renewable energy this year, up from 10% in 2021. And the company noted the InfluenceMap analysis does not account for investments outside of its Renewables and Energy Solutions division -- investments such as electric vehicle charging, biofuels and sustainable aviation fuel, all of which climate scientists have said are important in the effort to wean off fossil fuel.

Still, InfluenceMap says the companies' imbalance between "green" messaging and investment is striking.

It appears to be part of a "systematic campaign to portray themselves as pro-climate to the public," InfluenceMap program manager Faye Holder told CNN. "In the meantime, what we see is continued investment into this unsustainable energy system -- predominantly for fossil fuels."

InfluenceMap also estimated the companies are spending around $750 million each year cumulatively on climate-related communication activities, based on the number of communications staff the companies employ. The think tank said in a statement that figure doesn't include the cost of external advertising or PR agencies, so the true amount is likely "significantly higher."

"It seems to be just an evolution in the tactics that Big Oil is using to try to delay action on climate change," Holder said.