"The Washington Post story today that we actually hacked the Qataris is also not true," he told the London-based think-tank Chatham House.
Qatar's emir, Sheikh Tamim bin Hamad al-Thani, was quoted in May as praising Gaza's ruling Hamas movement and calling Iran an "Islamic power".
Saudi Arabia, the United Arab Emirates, Bahrain and Egypt imposed sanctions on Qatar on June 5, cutting diplomatic and transport ties with the tiny Gulf monarchy, after accusing it of financing militant groups and allying with their regional arch-foe Iran. Doha denies the accusations.
However, Gargash said the UAE would not escalate its boycott by asking companies to choose between doing business with it or with Qatar.
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