The Israeli government is embarking on a low-profile campaign against Qatar, which has emerged as the main backer of Hamas.

The campaign is neither full-scale or official due to the close ties between Washington and Qatar. One of the key elements of the diplomatic drive will be to raise questions over Qatar's suitability to host the 2022 World Cup.

Estranged from Iran in the wake of the Syrian Civil War and from the new Al-Sisi government in Egypt, Hamas has increasingly fallen back on the Qataris. According to Israeli intelligence, some of the millions of dollars that the emirate has poured into Hamas coffers over the years has been used to finance Hamas's military infrastructure.

Hamas political bureau chief Khaled Mashaal currently resides in Doha and the Qatari news channel, Al Jazeera, is supportive of the movement.

Last week, as the Israeli and Palestinian delegations tried and failed to reach a ceasefire deal in Cairo, Palestinian sources accused Qatar of directing Mr Mashaal not to agree to a deal which did not include any role for the emirate.

Qatar is increasingly being seen in the region as the bastion of "political Islam" with its support for Hamas, the Muslim Brotherhood and Islamist groups such as Jabhat al-Nusra in Syria.

While Qatar has been mentioned as Hamas's chief supporter in speeches by senior Israeli officials and politicians, the government has refrained so far from calling for diplomatic sanctions, largely due to the close ties between Washington and Doha.

Another difficulty for Israel is that if the emirate were to be stripped of the 2022 World Cup, pressure would grow for Fifa to move against Russia, which is due to host the event in 2018 and has strong strategic ties to the Jewish state.

Israeli envoy to the UN Ron Prosor recently described Qatar as a "Club Med for terrorists", adding that "one has to question Fifa's decision to reward Qatar with the 2022 World Cup".

Israeli officials also said this week that they would like to draw more attention to the abuse of labourers working on World Cup infrastructure in Qatar.