* Q1 Kumba Iron Ore production down 27 pct
* De Beers diamond production cut by 10 pct (Adds comments, background, share price)
By Mamidipudi Soumithri and Clara Denina
LONDON, April 21 (Reuters) - Anglo American Plc reported lower first-quarter production across most of its mining businesses on Thursday ahead of its annual meeting, where shareholders have been urged reject CEO Mark Cutifani's pay.
Falling commodity prices have hit the company's production and its share price, prompting investor advisory groups such as ShareSoc and Institutional Shareholder Services to question Cutifani's pay package - 3.4 million pounds ($4.88 million) in 2015 - which they say is too high.
The criticism of Cutifani's salary illustrates increasing pressure on bosses over high pay. Last week, a big percentage of shareholders in BP voted against chief executive Bob Dudley's $20 million pay deal for 2015.
"Given what the stock has done over the past couple of years, it (Cutifani's salary) seems a bit high," Nik Stanojevic, equity analyst at Brewin Dolphin, said.
"More broadly, there is probably an issue of corporate governance where there is a case to say that pay is not always in line with investors' interests," he said, speaking about companies in general.
Anglo's shares were down 75 percent in 2015, their fifth straight annual loss. They have risen in the first quarter.
Anglo American, the world's fifth-biggest diversified mining group by value, embarked on a major overhaul in February to cope with weak prices and demand, which includes the sale or closure of its iron ore, coal and nickel businesses.
The company said in the first quarter, iron ore production at its Kumba Iron Ore Ltd business fell 27 percent as its Sishen mine moves to a lower cost pit configuration.
It cut diamond production at its De Beers division by 10 percent to 6.9 million carats, due to low prices, while the sale of its Norte assets in Chile last year resulted in a 15-percent fall in copper production, the company said.
But nickel production was up 67 percent and platinum production rose 4 percent.
Anglo's shares were down 1 percent, underperforming the rest of the mining sector.
"Overall, this is a weak production report, across most key commodities - production volumes for iron ore, metallurgical and thermal coal, copper, nickel and platinum were all below our estimate - typically 5-7 percent below expectation," Canaccord Genuity said in a note.
Anglo American has been downgraded to 'junk' territory by credit rating agencies Fitch Ratings, Moody's and S&P, which cited the prolonged downturn in commodity prices, negative cash flows at many of the company's mines and uncertainty about the execution of the debt reduction. ($1 = 0.6969 pounds) (Reporting by Clara Denina in London and Mamidipudi Soumithri in Bengaluru; Editing by Gopakumar Warrier, Veronica Brown and Jane Merriman)