(Reuters) - Russian cyber security firm Kaspersky Lab said on Thursday that it has expanded its relationship with global law enforcement agency Interpol, agreeing to share threat data to help police fight cyber crime.  The company disclosed the agreement as the Kremlin dismissed claims by several U.S. newspapers that Israeli intelligence officials had determined that Russian government hackers were using Kaspersky s software for espionage. The reports were the latest in a series alleging the company and its founder, Eugene Kaspersky, have close ties to the Kremlin. Reuters has not been able to validate those claims.  Kaspersky has repeatedly said it has not helped Russia or any other government engage in espionage.  Kremlin spokesman Dmitry Peskov said on Thursday the Russian government believes the allegations against Kaspersky are without merit. He said that allegations, in articles in the New York Times, Washington Post and Wall Street Journal, were  absurd.    The government has not had and does not have any connection to such activity,  he said.  The accusations are ungrounded and unproven.  