Speaking at the Chatham House worldwide affairs think tank in London, Gargash repeated claims - denied by Qatar - that the country funds extremists.
Yousef al-Otaiba, the UAE ambassador to Washington, said in a statement that his country "had no role whatsoever in the alleged hacking", describing the article as "false", the Post said. We've said we are not there to escalate.
Qatar said at the time that it had been hacked by unknown entities. Qatar strongly denies the allegations.
"We've sent a message to Qatar".
"We need a regional solution and worldwide monitoring", he added while making remarks in London.
Gargash said there was a broader problem with financing for extremists in the Gulf but that countries like Saudi Arabia were "dealing with it".
Regarding the possibility of Qatar being excluded from the GCC, Gargash said: "The GCC is in crisis and I don't think it serves our purposes to say let's take Qatar out".
In late June, Kuwait, as a mediator in the crisis, handed over to Qatar the ultimatum of the four Arab states with 13 demands, including the requests to severe Doha's relations with Tehran, close Turkey's military base in Qatar and shut down the Al Jazeera TV channel, as well as to end support for the Muslim Brotherhood, a terrorist organization banned in Russian Federation. "But we can not have a member who is undermining us and supporting extremism", he said.
The falsified news report which surfaced in late May quoting Qatar's Emir Tamim bin Hamad al-Thani as praising Hamas, Hezbollah, Iran and Israel was a sign of the row that was to erupt two weeks later: the quotes were met with a particular storm of criticism by Saudi Arabia and the UAE, which in retaliation blocked Qatari-owned al-Jazeera from broadcasting. It is still unclear whether Qatar's other neighbours were also involved in the attacks.
The United Arab Emirates orchestrated the hacking of a Qatari government news site in May, planting a false story that was used as a pretext for the current crisis between Qatar and several Arab countries, according to a Sunday report by The Washington Post.