Greek officials have not gone into detail about the latest reform list. Sakillarides said only that it would not contain recessionary measures but structural changes.
The reforms are deeply sensitive for Tsipras, who came to power in January pledging to end austerity policies but was forced to accept an extension to a hated bailout program under the threat of a banking collapse.
Greece has received two bailouts totaling 240 billion euros since 2010 but its economy has shrunk by 25 percent partly due to austerity measures imposed by the lenders. One in four Greeks is out of work, and more than half of all young people.
Tsipras discussed the reforms with Merkel in Berlin on Monday. Sakellaridis said that in a four-hour working dinner they discussed only the outline without going into depth.
Both leaders voiced mutual goodwill during a visit that appeared to have cleared the air after weeks of public acrimony between Athens and Berlin.
German Foreign Minister Frank-Walter Steinmeier said after meeting Tsipras on Tuesday that an improved climate between the two countries would help start serious negotiations for a solution to Greece's debt problems.
The politician told reporters this alone would not solve Greece's financial problems, but it was "no doubt a precondition to begin serious talks in the coming days".
Greek financial markets rallied. The two-year bond yield fell nearly 2 percentage points on the day to below 20 percent.
A spokesman for the European Financial Stability Facility bailout fund said Dijsselbloem had asked the agency to review the Greek case for the cash refund, and had also asked the Eurogroup Working Group to work on the issue.
The move appeared to be a gesture of encouragement to Tsipras after euro zone ministers previously said Athens would get no more money until its reforms were approved by the Eurogroup and implemented to the satisfaction of the creditors.
The source familiar with the government's cash position said Athens had lately relied on repo transactions - where it borrows money from state entities - to cover its cash crunch, but could continue to rely on that only for a few more weeks.
"Although it will be hard, the country can make it without help until about April 20, using the short-term borrowing from public entities," the source said.