Total investment in the property was some £115 million (about $185 million), reflecting a price of about £623 ($1,005) per square meter.
Harel will own 49% of the rights to the building, and Ares will hold the remaining 51%.
The purchase was mostly financed from reserves against return-contingent liabilities (money from life assurance policies and pension funds) and partly from nostro funds.
The building has 10 stories (above two basement floors) with a high finish level and measures 183,727 square feet (about 17,069 square meters). It is currently leased.
Ares manages assets worth some $8 billion. The company employs some 130 investment experts, 70 of whom are professional investment consultants.