An Israeli official denied as “baseless” reports that linked Israel to a computer virus that was used to spy on the nuclear talks with Iran.

“The international reports of Israeli involvement in the matter are baseless,” Deputy Foreign Minister Tzipi Hotovely told Army Radio.

Kaspersky Lab, a computer security company, suggested on Wednesday that Israel had used a new variant of an internet worm, dubbed “Duqu 2”, to hack into networks of luxury hotels that hosted the negotiations between Iran and world powers.

Israeli Prime Minister Benjamin Netanyahu is a hardliner against efforts to reach a nuclear deal with Iran, claiming Tehran would not abide by provisions of the deal and that a lifting of sanctions would be used by Tehran to further its military purposes.

Hotovely on Thursday reiterated the Israeli government’s opposition to such a deal, Xinhua news agency reported.

“What is much more important is that we prevent a bad agreement where at the end of the day we find ourselves with an Iranian nuclear umbrella,” she said.

Iran and six major world powers, which struck a framework agreement last April, are seeking to reach a final deal by June 30 under which Tehran would restrain its nuclear programme in exchange for relief from sanctions.