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May 8 (Reuters) - Britain's Intertek ITRK.L on Friday rejected a sweetened 8.93 billion pound ($12.12 billion) takeover proposal from Swedish private equity firm EQT AB EQTAB.ST, saying it undervalued the product testing company and carried high execution risk.

EQT submitted a revised bid of 58 pounds per share earlier this week after its previous two proposals were rejected for undervaluing the company. The previous bids were for 54 pounds per share and 51.50 pounds per share.

If EQT buys Intertek, this would be the UK’s second‑largest private equity takeover, trailing only KKR's KKR.N 11.1-billion-pound acquisition of Boots in 2007, according to M&A data and intelligence platform Mergermarket.

($1 = 0.7368 pounds)