The sources said the negotiations were at an "intermediate" stage: it is possible no deal will be done.
No details could be obtained about the potential buyer, but rumors have been circulating for weeks that a global telecommunications has been sniffing.
Reports that the potential buyer is Nortel Networks were denied. ADC Communications was also mentioned.
Koor and Clal both belong to Nochi Dankner's IDB (TASE: IDBH) group.
In March 201, when ECI (then controlled by Koor) was in trouble as the hi-tech crash brought telecoms capex grinding to a halt, a group headed by Shlomo Dovrat bought holdings in the company and orchestrated a turnaround. The result was that Koor's value tripled.
The group of investors included Aharon and Shlomo Dovrat, Avi Zeevi and Harel Beit-On, and Ofer Hi-Tech. They invested $50 million in ECI for 12.5% of its shares. The group is now expected to join Clal Industries in exiting their investment.
An ECI spokeswoman said that the company does not comment on rumors.
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