A committee of MEPs also called on Friday for a thorough investigation.
Greece's supreme court has called for an investigation into a wiretapping case that has rocked the country for months, following revelations that more political personalities were illegally wiretapped.
The left-leaning weekly Documento claimed in a report on Sunday that former prime minister Antonis Samaras as well as the current ministers for foreign affairs, finance, development, labour and tourism were victims of wiretapping.
Vangelis Marinakis, a prominent mogul with media and shipping businesses as well as two football clubs, was also reportedly wiretapped.
The weekly, which has links to the left-wing opposition party Syriza, said it had information from "two people who had a key role in the surveillance".
The newspaper's editor-in-chief, Kostas Vaxevanis, said he would testify on Monday.
According to Documento, the Predator malware was used, along with technology used by the Greek intelligence service (EYP), to infect the phones not only of the targeted individuals but also of some of their relatives.
The government denied this, saying that the newspaper had no evidence, but nevertheless called for an investigation the day prior.
A committee of members of the European Parliament meanwhile called on Greece on Friday to conduct an "urgent and thorough" investigation into the illegal wiretapping case, which has poisoned the political climate in Greece in recent months.
Some of those targeted are influential members of the conservative ruling New Democracy party and potential rivals for Prime Minister Kyriakos Mitsotakis.
The case broke in July when Nikos Androulakis, an MEP and leader of Greece's Socialist Party, filed a complaint saying there had been repeated attempts to tap his phone using Predator spyware.
Two journalists and another prominent opposition politician later revealed that they had also been victims of surveillance by the Greek secret service.
The scandal led in August to the resignation of the head of the secret service and a nephew and adviser to the prime minister.
The government acknowledged the surveillance of Androulakis, without giving reasons, but denied the use of illegal software.