Washington, D.C., is now just hours away from legalizing marijuana in the district. Small amounts of pot use and possession will be allowed starting at 12:01 a.m. Thursday, Mayor Muriel Bowser confirmed in a Wednesday news conference.

Bowser said the plan would proceed despite earlier warnings from two congressional Republicans that approving pot would break federal law -- and possibly result in the mayor's arrest. She pointed to the broad voter support for Initiative 71, which legalizes limited doses of marijuana for personal, non-medical purposes.

"Our government is prepared to implement and enforce Initiative 71 in the District of Columbia," Bowser, a Democrat, told reporters alongside council members, Police Chief Cathy Lanier and city Attorney General Karl Racine.

“We would encourage the Congress to not be so concerned about overturning what 7 out of 10 voters said should be the law in the District of Columbia,” she said.

On Tuesday, top Republicans on the House Oversight Committee reminded Bowser that a clause tucked into the $1.1 trillion federal spending bill barred the District of Columbia from spending funds to make pot legal or reduce legal penalties. Congress has direct oversight over the district.

Reps. Jason Chaffetz, R-Utah, and Mark Meadows, R-N.C., sent a letter to Bowser warning her that legalizing marijuana would be "in knowing and willful violation of the law."

But Bowser contends that Initiative 71 was officially certified before the clause was adopted in December. The 30-day window for Congress to interfere with the initiative's implementation ends Thursday.

D.C.'s pot initiative allows adults 21 years or older to posses up to 2 ounces of marijuana and grow six plants. Sales are still illegal, but transfers of up to 1 ounce are allowed. Paraphernalia such as bongs and pipes are permitted, but public smoking is not. Bowser clarified Tuesday that "pot cafes" like those flourishing in Amsterdam would not be allowed in the district.

Following the Wednesday conference, top Democrats spoke out in support of the marijuana measure.

House Minority Leader Nancy Pelosi, D-Calif., said she agreed with Bowser that the clause in the federal spending plan does not repeal or block Initiative 71. “It is very troubling that Republicans would threaten elected District officials for implementing the measure resoundingly passed by the District of Columbia’s voters," she said in a statement cited by RollCall.com.