Israel on Sunday appealed to Russian President Vladimir Putin to pardon an Israeli-American who has been sentenced to seven-and-a-half years in jail after she was caught with cannabis in her checked luggage while transiting at Moscows Sheremetyevo airport. Naama Issachars case has opened up an unusually public rift between Israel and Russia. Her family says she is being punished disproportionately to pressure Israel into freeing a Russian held in Israel on a US extradition request. Issachar was arrested in April during a layover in flights from India to Israel. Russian police found 9 grams of cannabis in her luggage, her family says. On Friday, a Russian court sentenced her for drug smuggling. "Naama made a grave mistake and has admitted her crime, but in the case of a young woman with no criminal record, the severe sentence handed down will have a deeply destructive impact on her life," Israeli President Reuven Rivlin wrote in a letter to Putin distributed by his office. "I am appealing to your mercy and compassion with a request for your personal intervention to grant her an extraordinary pardon." The letter, published on Rivlins Twitter account, noted recent Russian help in locating the remains of an Israeli soldier killed by Syrian forces in a 1982 battle. Putin would be informed about the letter and consider the request once the Kremlin receives it via diplomatic channels, spokesman Dmitry Peskov told Reuters. Russian and Israeli media have reported that Moscow is seeking an exchange to prevent Israel from extraditing to the US Aleksey Burkov, a Russian citizen detained in Israel since 2015 for alleged cyber crimes and credit card fraud.