Seven Belgian pharmaceutical executives may face trial on suspicion of supplying an important ingredient for making crystal meth to a Mexican drug cartel.

Belgium's federal prosecutors refused to provide the identities of the people involved or the companies that employ them.

"We are asking for them to be referred to court and the decision will be made on April 5," a spokesman for Belgium's federal prosecutors announced on Wednesday.

Companies Admit Involvement

Prosecutors said that the companies made numerous deliveries of ephedrine or pseudoephedrine, which is a substance normally found in cough syrup and nasal decongestants. Ephedrine is also used to make meth, an extremely addictive stimulant drug.

Sterop, a small pharmaceutical group based in Brussels, admitted via a spokesman of its involvement in the case, but the firm insisted that it had been duped by intermediaries and they didn't break the law. Belgian pharmaceutical wholesaler Andacon also admitted its connection with the case due to its deliveries of pseudoephedrine in tablet form back in 2006.

The companies acknowledged that pseudoephedrine did not necessitate an export license during that time, but the Mexican company that the Belgians made transactions with one. The firms noted that they are planning to ask for the dismissal of the case against their client.

Belgium's law dictates whether a specific court will allow cases brought by a prosecutor go to trial.

Mexico's Meth Production Soars

A recent report found that Mexican drug cartels are increasing their meth production as a response to the growing demands of the consumer market in the United States.

A report from the International Narcotics Control Board, or INCB, stated that Mexican authorities seized more than 19 tons of methamphetamine in 2014, a 34 percent growth from 2013. Authorities also found 131 meth laboratories, which were mostly situated in the states of Guerrero, Michoacán and Sinaloa.

According to the report, seizures of meth at the U.S. border have gotten bigger by a factor of three since 2009. Mexico's drug gangs have also developed smarter and more sophisticated ways to avoid detection from authorities. The INCB said that criminal groups dilute meth in a liquid solvent, a process which makes detection of the drug difficult.

Drug cartels have long supplied cocaine and marijuana to the U.S. consumer market, InSight Crime reported. Cocaine consumption, however, has plummeted in the United States by as much as 50 percent, while the country's relaxation of marijuana laws has driven down demand for marijuana cultivated in Mexico.

Mexican crime groups earn billions of dollars from the drug trade. Authorities revealed that drug cartels profit over $60 billion from their sales in the United States.