Updated

Mexican President Felipe Calderon has signed into law a ban on large cash transactions as part of an effort to fight money laundering that experts estimate may amount to around $10 billion per year in Mexico.

The bill forbids buyers and sellers from giving or accepting cash payments of more than a half million pesos ($38,750) for real-estate purchases. It also forbids cash purchases of more than 200,000 pesos ($15,500) for automobiles or items like jewelry and lottery tickets.

The fact that the law took two years to move through Congress illustrates the sensitive nature of such rules in a society where small businesses and retailers, as well as gangsters, have long conducted many of their transactions in cash. It goes into effect in about 90 days.