Details of the plan were not released.
Russian media reports suggested that the leaders agreed to respect a new ceasefire line that concedes territorial gains to the pro-Russian rebels.
The original peace agreements signed in September in Minsk are in tatters after the rebels launched an offensive in January.
Merkel and Hollande began their surprise initiative on Thursday in Kiev, holding talks with Poroshenko.
Before the Moscow talks, both leaders cautioned that there was no guarantee of success.
"We know it is completely open whether we'll manage to achieve a truce ... or if further talks will be required," Merkel said in Berlin.
She and Hollande were not neutral mediators but acting in the interests of "Germany, France and, first and foremost, Europe", Merkel said.
German Defence Minister Ursula von der Leyen warned that arms shipments to Kiev, as considered by the United States, would not be helpful to solve the "hybrid war" that Russia was waging in Ukraine - a combination of intelligence and military operations, political destabilisation and a propaganda campaign, all of which are present in Ukraine, she said.
"A focus on arms alone can be a fire accelerant that only removes us further from a solution," von der Leyen told the Munich Security Conference.
Merkel and Poroshenko were to address the conference last night in Munich, with US Vice-President Joe Biden and Russian Foreign Minister Sergei Lavrov.
Tomorrow, Merkel is due in Washington DC for talks with US President Barack Obama.
A White House spokesman said German opposition to arming Ukraine "matters a great deal" to Obama.
The conflict in eastern Ukraine has claimed more than 5000 lives since last year, including 200 in the last three weeks, according to the United Nations.
- AAP
