The company has been handed a below-average environmental, social and governance score by one of the world's biggest credit ratings agencies, as the miner's decarbonisation plans and strong safety record fail to offset the emissions intensity of its iron ore business, according to the Australian Financial Review.

Standard & Poor's on Thursday assigned the group an ESG evaluation of 66 out of 100.

It combines an assigned ESG profile score of 58 and S&P's "preparedness opinion" of eight.

The assessment puts FMG below S&P's average score of 67 from more than 100 entities globally, albeit there are few mining companies assessed to date.

This is despite FMG's lofty ambitions of reaching net-zero Scope 1 and 2 emissions by 2030, using green hydrogen, ammonia and electricity to decarbonise its mining operations. 

Meanwhile Bell Potter Securities analyst David Coates released a note overnight, lowering FMG's price target from A$19.75 to $18.33, even with the company's first half of iron ore shipments being ahead of the firm's forecasts. 

"In our view, the December 2021 quarter and the start of CY22 have marked the start of an inflection point for FMG," Coates wrote.

He noted that the company's strategic objective of becoming, what FMG says, will be a vertically integrated green energy and resources company, is being "aggressively" pursued by a plethora of deals and agreements by Fortescue Future Industries, and now directly by FMG after it announced earlier this week that it was acquiring Williams Advanced Manufacturing.

Most of the deals struck by FFI at this stage have been non-binding memorandums of understanding. 

Outgoing FMG CEO Elizabeth Gaines told reporters on a call on Tuesday that the purchase of WAE supported the company's decarbonisation targets and said the acquisition was well and truly within FMG's remit, given that its mining fleet was up for renewal this decade.

"FMG has been working with WAE since last year and we've indicated in the past we need to align our fleet renewal with investment in our green fleet," she said.

However Coates wrote that the acquisition was representative of many of the company's exhaustive list of agreements. 

"While it has strategic value to FMG meeting its "net-zero by 2030" goals, it generates negligible EBITDA and its value accretion to the core business cannot be quantified," he wrote. 

"From a valuation perspective this drives increased capital expenditure for no measurable return. 

"This is creating uncertainty in the market and emerging as an increasing potential overhang on FMG's share price - until returns can be quantified."

Coates said larger grade and quality discounts and incrementally higher cash costs are the prime drivers of 17% and 7% cuts to Bell Porter's earnings forecasts for FMG for FY22 and FY23 respectively. 

The firm lowered its recommendation to "hold".

Gaines has repeatedly stated that FFI's primary goal will be decarbonising its parent company, saying the profits would come from the premium customers will pay for their zero-emission products. 

"If you think about our goal to become carbon neutral by 2030, we see that as a significant commercial opportunity for Fortescue to generate more profits to lower our costs and get a premium for our iron ore, which will be green," she told shareholders at the company's AGM in November.

She added that not decarbonising could risk the company facing steeper costs as future government's and regulatory bodies looking to cut emissions.