The Senate’s top budget writer again expressed reservation Thursday toward Gov. Maura Healey’s plan to use surplus dollars from the pandemic to pay down massive shelter costs and a deficit this fiscal year.

Growing doubt in the Legislature around handing more money to the shelter system comes before the governor has officially filed a bill  with the Legislature, though she did lay out detailed ideas in a report to top Democrats in December.

Senate Ways and Means Chair Michael Rodrigues said he is “very protective” of reserve funds.

“I am very protective of the reserve funds that we’ve worked hard to build up, that we’ve acted responsibly over the years to build up. So I’m very protective of them, including the stabilization fund,” the Westport Democrat said, echoing comments he made last week.

In the first bi-weekly report submitted to the Legislature last month on the emergency shelter system, Healey floated using $700 million in surplus revenues held in a transitional account to cover a $224 million budget deficit this year and a $915 million shelter tab in the next.

Administration and Finance Secretary Matthew Gorzkowicz and Housing Secretary Ed Augustus said the shelter system’s funding challenge is a two fiscal year “problem.”

“The state has the resources available in transitional escrow to put a plan in place that will address FY24 and much of FY25 without requiring offsetting budget cuts to other programs to meet the spending requirements of the family shelter crisis,” the two secretaries said in the report.

Gorzkowicz and Augustus said in the Dec. 18 report that the administration planned to file a supplemental budget in the “coming weeks” in an effort to put the dollars to use. About a month later, a spokesman for the Executive Office of Administration and Finance said Thursday there was no update on timing.

Not all leaders on Beacon Hill are expressly onboard with the idea of shuttling more money to the shelter system.

House Speaker Ron Mariano expressed hesitancy Wednesday with allocating more dollars to the emergency assistance shelter system as Massachusetts faces revenue headwinds. He did not directly address whether he agreed with Healey’s proposal.

“I mean, obviously, it’s a concern as revenues continue to bottom out and flatten. It becomes harder and harder to support some of these things,” he said.

The Healey administration this week said Massachusetts is expected to collect $1 billion less in revenues than originally anticipated when lawmakers crafted the fiscal year 2024 budget.

In an effort to balance the budget, Healey cut $375 million in spending this fiscal year and scraped up $625 million in other revenues to close the gap. But impending financial challenges have raised questions about shelter spending, which have more than tripled in the last year.

Rodrigues said Healey’s decision to cut the budget this fiscal year was “responsible” and argued the economy is expected to grow next fiscal year, though at a much smaller percentage than previous year.

“The governor had to take action that no governor wants to take action on in making cuts midterm. She is the fourth government in a row that had to take those actions,” he said. “I think she did so in a responsible manner.”