Government health officials in Washington, D.C., may foot the bill for medical marijuana for the city's poorest patients, according to a new rule proposed by the Department of Health.

In a public notice filed last week and first reported by the Washington Times, the city DOH proposed a rule that would mandate that medical marijuana dispensaries adjust the price of pot on a sliding scale for patients who cannot afford it.

The dispensaries would have to use 2 percent of their revenue in order to make up for the difference in price, according to the rule. Patients who could prove to the city that they earned 200 percent or less of federal poverty level wages could qualify to purchase medical marijuana on a sliding scale.

The pot would have to be discounted at least 20 percent, the rule states.

According to the Times, medical marijuana currently costs $380 to $440 an ounce in the city, which allowed sales to begin last month.

The Department of Health did not immediately return calls requesting comment from ABC News.

The rule is set to take effect in 30 days.