The president of the UN General Assembly, who is locked in a bitter spat with Israel, said on Monday he had received death threats which are being investigated by UN security officials. Miguel d'Escoto Brockmann received threats after he tried to prevent Israel's UN ambassador Gabriela Shalev from speaking at a plenary session of the assembly, a statement released by his spokesman, Enrique Yeves, says. "Very serious threats have appeared on the Internet against the life of the president of the General Assembly" the statement also affirms, adding: "This matter is being looked into by pertinent authorities." The statement also reacts to Israeli press reports that D'Escoto tried to prevent Shalev from speaking last week at a plenary session to mark the 60th anniversary of the Universal Declaration of Human Rights. "This is a malicious and absolute lie that could best be characterized as 'slander'," D'Escoto said through his spokesman. "Information from the media attributes senior diplomatic officials in the Permanent Mission of Israel to the United Nations as the source for this irresponsible accusation." D'Escoto also slammed Israel's "arbitrary detention" and denial of entry to Richard Falk, the UN's special rapporteur on human rights, into the Palestinian territories. Falk, who is the UN's monitor of human rights in the Palestinian territories, last week prompted Israel's ire when he said its policies against people in the territories amount to a "crime against humanity." UN officials said Falk was sent back to Zurich upon arrival at Ben Gurion Airport, near Tel Aviv, on Sunday. Asked to comment on d'Escoto's remarks, Mirit Cohen, the spokesperson for Israel's UN mission said in a statement: "The role of the president of the General Assembly should be to unite the international community and promote shared interests and values."