Russian Foreign Ministry warned Monday citizens to exercise extra caution while travelling abroad to avoid potential detention under U.S. warrants. \"Russian citizens are advised to refrain from the travels abroad, especially to the countries which have readmission agreements with the U.S.,\" the ministry said in a statement. It noted that the advice has been mostly applied to the Russian citizens who may expect to be on the U.S. authorities\' wanted list. \"The court hearings with those (Russians) effectively abducted to the U.S. are biased. They are based on a shaky legal ground and have clear accusation bias. As a rule, these hearings end up with indictments,\" the statement said. Russia said despite its diplomatic missions assist fellow citizens in need, the court hearings nevertheless result in criminal indictments. Recently, several countries, including Lithuania, Spain, Costa Rica, Dominican Republic, arrested and handed over to the U.S. law enforcement agencies the Russian citizens wanted by Washington on various allegations.