Ukraine and pro-Russian rebels on Thursday said their forces were respecting a ceasefire aimed at halting a recent spike in violence in time for the start of the new school year.
The warring sides agreed their latest temporary truce on August 26 in Minsk, the Belarussian capital where a February 2015 peace deal was signed with the help of the leaders of Germany and France.
But that agreement and the subsequent series of temporary truces have done little to halt a 28-month war that has claimed nearly 9,600 lives and driven about two million people from their homes.
The previous ceasefire announcement in April was later followed by two months of what monitors from the Organization for Security and Co-operation in Europe (OSCE) described as fighting that approached a full-scale war.
Ukrainian President Petro Poroshenko said in a statement that the September 1 truce "was holding as of 12:05 pm (0905 GMT)".
Militia commander Eduard Basurin confirmed on the rebels' official news site that there were "no violations after midnight".
French President Francois Hollande and German Chancellor Angela Merkel said in a joint statement Thursday that they hoped that this marked "the beginning of a lasting ceasefire".
The announcements may help calm tensions that were stirred by Moscow's accusations last month of Ukraine plotting to invade Crimea -- the Black Sea peninsula Russia annexed in March 2014.
Russian President Vladimir Putin had vowed retaliation and Poroshenko said he feared the resumption of the type of warfare that killed dozens on a nearly daily basis in 2014.
Russia denies plotting or backing the conflict in retaliation for its former Soviet neighbor's ouster of its Moscow-backed leadership in a February 2014 pro-EU revolt.
But Washington and Brussels have slapped stiff economic and other sanctions against Russian state companies and officials over Moscow's seizure of Crimea and alleged intervention in eastern Ukraine.
The United States on Thursday announced a long list of fresh sanctions against Russia, including against Bank Rossiya -- often referred to as Putin's personal cash fund.
It also targeted a company building a bridge between mainland Russia and Crimea that Ukraine and the West both oppose.
Rays of hope
Some signs emerged late on Thursday that this ceasefire may be more substantive and lasting than previous agreements.
The OSCE said it had coordinated an evening video conference with Russian and Ukrainian representatives as well as rebel leaders from the separatist Lugansk and Donetsk regions.
"All participants... expressed their firm support to the recommitted ceasefire reached," the OSCE statement said.
"They assured that the ceasefire has the support from the highest political level," it added.
That phrase appeared to refer to both Putin and Poroshenko -- two leaders whose relations continue to sour and direct contacts grow increasingly rare.
There was no immediate response to either the new US punitive measures or the OSCE statement from Moscow.
Putin is expected to hold separate talks with Merkel and Hollande about Ukraine on the sidelines of the G20 summit that will be held this weekend in China.