It gave no other details after a second day of talks on Poroshenko's proposals for ending a crisis in which scores of people, including pro-Russian separatist fighters and government forces, have been killed in east Ukraine since April.
"As a result of the work, the sides reached a mutual understanding on key stages of the implementation of the plan and on a list of priorities which will contribute to a de-escalation of the situation in the Donetsk and Luhansk regions of Ukraine," the Ukrainian Foreign Ministry said.
Moscow did not immediately comment and Poroshenko has made few details of his plan public.
The talks are being mediated by the Organization for Security and Cooperation in Europe, a security and human rights watchdog. At the first talks on Sunday, with Russian envoy Mikhail Zurabov, Poroshenko said violence must end this week.
The Foreign Ministry did not say who had attended Tuesday's talks, but said the "contact group" would hold further meetings on the crisis, which has caused the worst standoff between Russia and the West since the Cold War ended.
Since Poroshenko was elected president on May 25, the Ukrainian army has stepped up military operation to take back buildings seized by pro-Russian separatists in several towns and cities in mainly Russian-speaking east Ukraine.