FILE -In this Monday, April 6, 2015 file photo, .'(AP Photo/Patrick Semansky) (Patrick Semansky/AP)

Maryland Gov. Larry Hogan (R) has scheduled a major announcement about “transportation infrastructure” for Thursday afternoon, raising speculation that he has made a decision on whether to build the long-planned Purple Line project, a 16-mile rail line that would connect two Washington suburbs.

An aide would not confirm on Wednesday if the news conference would address the future of the Purple Line, which would run from New Carrollton in Prince George’s County to Bethesda in Montgomery. Earlier this week, the governor’s office said Hogan would make an announcement about the project before the end of the month.

Proponents of the Purple Line have been anxiously waiting to learn whether Hogan, who during the campaign questioned the $2.45 billion cost of the light-rail line, will move forward with a project that they say will create jobs and spur economic development.

The decision will be one of the biggest and most closely watched since Hogan took office in January. It forces the governor to wade into the political fray of transit versus roads, which is also one that pits the state’s rural areas against its densely populated urban centers.

Mapping the Purple Line

The governor is also considering whether to continue with plans to build a $2.9 billion light-rail Red Line in Baltimore.

Earlier this month, The Washington Post reported that Transportation Secretary Pete K. Rahn had recommended to Hogan that he approve building the Purple Line, at a cost that is lower than current estimates.

Rahn suggested reducing the $2.45 billion price tag by $300 million, and asking Montgomery and Prince George’s counties to pay a greater share of the costs.

Hogan has refused to comment on Rahn’s recommendation, repeatedly saying he would make a final decision by the end of June. He has repeatedly questioned whether the project is too expensive, and would take away too much money from road projects. He asked Rahn’s office to conduct a cost analysis to see if the transit line could be built at a lower cost.

On Monday, Hogan disclosed that he has been diagnosed with an advanced stage of non-Hodgkin’s lymphoma. He said he would continue working as much as possible during an aggressive 18-week chemotherapy regimen, which is expected to begin in coming days.

Thursday’s news conference will be his first appearance in the Statehouse since he shared his cancer diagnosis.

Spokesmen for Montgomery and Prince George’s County executives Isiah Leggett and Rushern Baker said neither was scheduled to be in Annapolis this afternoon.

Bill Turque contributed to this report.