The chairman of the Palestine Solidarity Campaign has been prevented from entering Israel.
Hugh Lanning was refused entry on Sunday, just a week after the Knesset passed a law banning foreign nationals who call for boycotts.
Lanning would likely have been barred prior to the introduction of the law due to a longstanding policy to refuse entry to boycott activists; however, border police told him he had been blocked due to the new legislation.
Gilad Erdan, Israel's Strategic Affairs Minister, also made explicit the link between the new law and the treatment of Lanning, saying on Sunday evening: "Those acting against Israel need to understand that reality is changing. No sane country would permit entry to the main activists calling for its boycott and who work leave it isolated."
A joint statement by the Interior Ministry’s Population and Immigration Authority and Ministry of Public Security highlighted PSC’s involvement with other groups who work to delegitimise Israel in the UK.
It also pointed out Mr Lanning met senior Hamas figures in Gaza in 2012, including top official Ismail Haniyeh.
Interior Minister Aryeh Deri said Israel was following a “determined policy that would no longer look the other way on activists who want to undermine its existence.”
A statement from the Israeli Embassy in the UK emphasised the PSC’s support for the BDS campaign.
It said Mr Lanning “is associated with the leaders of Hamas, which is designated as a terror group across the European Union; a group whose antisemitic charter calls for killing all Jews.
“Israel is seeking a peaceful resolution to its conflict with the Palestinians. Those who promote extremism should not be allowed to foment their hatred in Israel.”
He was expected to be put on a flight back to the UK overnight or on Monday morning.
A report into the group last month found dozens of leading supporters of the PSC engaged in antisemitic activity online.
The 79-page dossier revealed an antisemitic mind-set was prevalent among senior PSC members according to evidence collected over two years by David Collier, a Jewish blogger and activist.
Last week the PSC’s Twitter account was temporarily suspended after a message posted from it welcomed new Hamas leader Yahya Sinwar.
In a statement, the group said its account had been hacked and someone had sent messages “purporting to be from PSC expressing support for Hamas. The following day our Facebook account was also hacked into.
“Whilst we do not know who was responsible for the hacking, there is a history of NGOs and individuals campaigning for Palestinian rights being targeted for these attacks.
In a statement responding to the ban, Ben Jamal, director of the Palestine Solidarity Campaign, claimed Mr Lanning, 64, was the "first victim" of the new Boycott Law, and added that the group believed "he is now permanently barred from the country".
Mr Jamal said: "By introducing this law, Israel is violating fundamental freedoms essential to a democracy- the right to free speech, to criticise government policies and human rights violations, the right to advocate non-violent actions to address human rights abuses, the right of free movement and travel. A democratic country does not behave in the way Israel is behaving."
He urged the UK government to condemn Mr Lanning's deportation.
He said: "We call upon the British Government to make clear to Israel that it is not acceptable for it to ban entry to British citizens whose only crime is to advocate for human rights of the Palestinian people and to protest against policies that violate those rights .”
Jonathan Arkush, president of the Board of Deputies, said: "Israel has exercised the same power that the United Kingdom has to deny admission where it would be conducive to the public good. If Palestine Solidarity Campaign wants to avoid being treated like a pariah, it has to stop behaving like one.”