President Donald Trump signed the legislation in December 2019, significantly raising the business risk of linking up with the Syrian regime and its associates. Coming into effect on Wednesday, the act is part of the National Defense Authorisation Act. It is named after the codename of a photographer who took pictures of thousands of corpses of jailed dissidents who were killed or who died in regime jails. Under the new rules, the US executive is required to impose sanctions, including asset seizures, on many of those who do business with the Bashar Al Assad government, or are involved in the oil and construction sector in regime areas. Secondary sanctions associated with the act mean that companies or individuals who do not directly support the regime but who have links with those doing business with it, could be affected. Kelly Craft, the American ambassador to the United Nations, said this week that the Caesar Act is aimed at “bad actors who continue to aid and finance the Assad regime's atrocities against the Syrian people while simply enriching themselves.” Within 90 to 180 days from Wednesday, the legislation requires the US executive to: Hundreds of regime members and their associates are already under American and European sanctions. Americans have been banned for years for having links with the country’s oil sector, and from exporting to the country or investing in it.