US President Barack Obama made clear his "disgust" at anti-Jewish leaflets handed out in east Ukraine's main city, his top national security aide said Friday.
The pamphlets telling Jews to register or be expelled were distributed in the city of Donetsk and sparked global outrage and fears of a Nazi-style pogrom.
"The president expressed his disgust quite bluntly," said Obama's national security advisor Susan Rice. "I think we all found word of those pamphlets to be utterly sickening, and they have no place in the 21st century."
Rice said that Secretary of State John Kerry, who condemned the leaflets on Thursday in Geneva, had made US objections clear to Russian Foreign Minister Sergei Lavrov.
The pamphlets carried the stamp of the pro-Russian insurgency and signature of one of its leaders, from the self-proclaimed "People's Republic of Donetsk".
The US embassy in Kiev first raised concerns over the leaflets, which it said appeared to be an attempt to stir fear.
The chief rabbi in Donetsk said that he saw the leaflets as "provocation."
They contained a demand for every Jew to gather at the seized local administration building on May 3 to pay a fee of $50 (36 euros) to register or face the threat of being expelled from the region.
Jewish community on edge
Members of the Jewish community in the pro-Russian protest hub of Donetsk in eastern Ukraine said that they were left shaken by the distribution of tracts demanding the registration of Jews.
Concerns were evident, despite scepticism from Jewish leaders in the region and America's Anti-Defamation League, which combats anti-Semitism, that the pamphlets handed out in front of the synagogue on Tuesday were anything more than calculated "provocation" by unknown parties.
The ADL also condemned the "cynical and politically manipulative uses" of anti-Semitism accusations for political gain by both Russia and the Ukraine.
"One of the men insisted that we read some pamphlets that they had in their hands. We refused because he wouldn't remove his hood so they glued the fliers to the synagogue and left," said Leonid Krasnopoloski, 43.
The incident happened as around 20 Jews were leaving the synagogue after marking the second day of the Jewish festival of Pesach (Passover).
The three hooded men handing out the pamphlets were carrying a Russian flag and the symbol of the separatist "Republic of Donetsk", which has not been recognized by any countries.
"I have lived here for 40 years without any problem and now there is this phenomenon of the 'Russian spring' and immediately problems are surfacing," he said.
Anti-Semitic document a forgery?
But responding to the incident, Denis Pushilin, the pro-Russian protest leader whose signature was on the documents, strenuously denied that he had anything to do with the demands.
"The documents were handed out in our name but this was a provocation. My signature was forged," Pushilin said at a press conference on Friday.
Senior Jewish leaders in the region seemed to accept that the appearance of the anti-Semitic literature was likely designed to inflame tensions in Kiev's shadowy struggle against the eastern separatists.
"What happened of course smells of a provocation. As to who is behind it - that is an open question," the region's chief rabbi Pinkhas Vyshedski said.
But reports of the anti-Semitic tracts sparked international concern with US Secretary of State John Kerry branding the distribution of the pamphlets as "grotesque".
"In the year 2014, after all of the miles travelled and all of the journey of history, this is not just intolerable, it's grotesque. It is beyond unacceptable," Kerry said on Thursday.
The head of the World Jewish Congress urged all sides in the conflict to refrain from using anti-Semitic propaganda to further political goals.
"All sides must ensure that any form of anti-Semitism is condemned and fought vigorously. Unfortunately, the Ukrainian Jewish community is caught up in a situation for which it bears no responsibility, and it needs to be protected against unfair attacks, no matter where they may come from," said WJC President Ronald Lauder in a statement.
Moscow has repeatedly levelled allegations of anti-Semitism at the authorities in Kiev, accusing them of being controlled by far-right groups that played a prominent role in protests to oust Kremlin-backed president Viktor Yanukovych.
The unrest in Ukraine has brought with it a rise in anti-Semitic attacks on the region's Jewish population, highlighted by such events as the stabbing of the Deputy Commander of ZAKA Kiev and Hatzalah Kiev Chairman Rabbi Hillel Cohen.
Tzvi Magen, the former Israeli ambassador to Russia, told Arutz Sheva on Wednesday night that Russia is orchestrating the confrontations in an attempt to seize greater control over Ukraine.
Russian slams 'unacceptable' US threats, as military masses
Meanwhile, events in eastern Ukraine continue to escalate, as Russia said its military is massed on Ukraine's doorstep and warned against further US sanctions as a deal struck with Washington appeared to stall because of intransigence by Moscow-backed rebels in the former Soviet republic.
A threat by US President Barack Obama that more sanctions would befall Moscow if the agreement - reached Thursday with Ukraine and the EU - failed was "absolutely unacceptable," Kremlin spokesman Dmitry Peskov told Russian television.
"Our Western colleagues are trying to push responsibility towards our side. But it must be underlined: it is a collective responsibility," he said.
He pointedly declared that "there are troops close to the Ukrainian border".
"Some are based there, others have been sent as reinforcements due to the situation in Ukraine," he added.
The comments appeared to be a warning shot to Washington that the situation could quickly degrade if Moscow were punished for a failed implementation of the accord.
The White House said it was watching Moscow to see if it is holding up its end of the deal.
"We expect and we will be watching whether Russia does or does not uphold its responsibility to use its very considerable influence to restrain and withdraw those irregular militia from the buildings and spaces that they've occupied," said National Security Advisory Susan Rice.
In a phone call on Friday with Russian Foreign Minister Sergei Lavrov, US Secretary of State John Kerry said the following days would be "pivotal", a senior State Department official said.
The top US diplomat stressed that "all illegal armed groups must be disarmed and all illegally seized buildings must be returned to legitimate owners," according to the official.