Federal prosecutors have opened a grand jury investigation into potential illegal lobbying efforts on behalf of Qatar, according to a report from Mother Jones. Sources told the magazine that federal law enforcement is scrutinizing a trip to the Gulf country by retired Marine Gen. John Allen paid for by Imaad Zuberi, a former lobbyist who pleaded guilty to lobbying charges, making illegal campaign contributions, and tax evasion. Mother Jones reported that former Trump national security adviser H.R. McMaster reportedly asked Allen to visit Qatar in an effort to mediate a growing rift between Doha and its Gulf neighbors, Saudi Arabia and the United Arab Emirates but the trip was reportedly paid for by Imaad Zuberi.