From an industry-wide marginal production cost of US$6150 a tonne in 2021, the cost of producing copper has risen to $8000/t, the bank said.
Some existing mines will struggle to trade profitably in the new and higher cost environment while projects in the planning stage could face delays as developers reassess new financial pressures.
It does not get any better on the revenue side of Citi's outlook with the copper price forecast to fall to $8500/t over the next three months, down another 5.5% on the latest price of $9000/t which is already 16.6% down on the March peak of $10,800/t.
"Cost support has historically been a pro-cyclical moving target, however this time might be different in the very near term given the supply shock emanating from the Russia/Ukraine situation," Citi said.
"Specifically, we estimate that copper marginal mining costs are on track to rise to around $8000/t during 2022 (up 30% from $6150/t during 2021), driven by higher consumables, diesel and power prices in particular.
"Indeed, falling copper prices are set to squeeze miner's margins in the near term. This is a dynamic true across metals markets."
The combination of rising marginal costs and a falling price prompted the bank to advise clients to "keep selling rallies near term".
Copper miners are not alone in being battered by the combination of rising costs and falling metal prices. Aluminium, nickel and zinc are also under similar pressures caused primarily by a slowdown in demand for commodities in China as the government in that country enforces draconian lockdowns to try and beat a growing Covid outbreak.
Citi said in last week's edition of its Metals Weekly report that near-term cautiousness had led to a downgrading of price forecasts.
"We see London Metal Exchange copper falling to $8500/t on a 0-to-3 months view, aluminium to $2700/t (it is currently $2802/t), nickel to $25,000/t ($26,449/t) and zinc to $3300/t ($3564/t) over the same period" the bank said.
"Chinese data is coming in worse than expected and the Fed remains hawkish.
"China's weakness is not just because of lockdowns but because policymakers have been behind the curve."
