MOSCOW/LONDON, May 13 (Reuters) - Around a dozen chief executives and chairmen of major U.S. and European corporations have pulled out of an economic conference in St Petersburg as pressure between Russia and the West grows over the crisis in Ukraine.
Eleven business leaders who were listed in late March as scheduled to attend the St. Petersburg International Economic Forum from May 22-24 are no longer on the programme on the forum's website.
Only one company said their executive's decision to stay away was due to political tensions with most refusing to give a reason. However, the cancellations come as the United States and Europe mull further sanctions on Moscow in relation to violence in Eastern Ukraine, which western governments have blamed in part on Russia.
Sanctions have already been imposed in reaction to Russia's annexation of Crimea.
The chief executives of oil producer ConocoPhillips, jet maker Airbus Group, Visa Inc, Aluminium group Alcoa, Siemens, Citigroup, Morgan Stanley, International Paper Company, Pepsi , Italian oil group Eni and the chairman of consulting group Bain & Company are among those no longer scheduled to attend the event.
Over a dozen Western business leaders, including Goldman Sachs Chief Executive Lloyd Blankfein, remain on the programme but sources close to some of the companies said, other bosses planned to pull out.
White House spokesman Jay Carney said earlier this month that U.S. officials had been discussing the event, Russia's answer to the Davos World Economic Forum, with business leaders, and had made it clear that attending would not be appropriate given "flagrant violations of a sovereign nation's territorial integrity."
Business sources said the withdrawal of CEOs from the forum, which is held "under the auspices" of the president, according to its website, could be seen as a sleight by Putin and could damage their companies' businesses in Russia.
"I am sure that the forum will be held in a friendly atmosphere and that any withdrawals will not spoil the atmosphere," said Deputy Minister of Economic Development Sergey Belyakov in a video interview posted on the St Petersburg forum's website.
"Many companies confirmed their participation and we have no problems with the quality of our participants or of the number. Around 6,000 participants confirmed - many top managers of Russian and foreign companies that are in Forbes and Fortune ratings," he said.
"I am surprised at the pressure coming from the White House administration. The only parties which will suffer will be American companies."
Belyakov said Russia understands the atmosphere in which American companies are making their decisions and said there would be no risks for those companies in Russia who cancel.
Spokespeople for Pepsi, Citigroup and Siemens confirmed their bosses had pulled out, and blamed scheduling clashes.
Spokespeople for Airbus, Conoco, Visa, Morgan Stanley, International Paper, Bain & Company, declined or were not available for comment.
Paolo Scaroni, Eni's CEO until earlier this month was due to attend but a spokesman for the Milan-based group said no decision had yet been taken on whether his successor, Claudio Descalzi, would attend.
The only company to link its decision to the political situation was Alcoa which said last week that CEO Klaus Kleinfeld was withdrawing "in light of the U.S. government's requirements".
A source close to Goldman Sachs said Blankfein was unlikely to attend. The bank declined comment.
(Additional reporting by Tim Hepher in Paris, Jens Hack in Frankfurt, Lisa Baertlein in Los Angeles, Anna Driver in Houston, Lauren LaCapra, David Henry, Ernest Schneyder and Lewis Krauskopf in New York, Ludmila Danilova in Moscow; editing by Anna Willard)