Putin and Macron talk again by phone, keeping diplomatic lines open.

The diplomatic push to avert a wider conflict between Russia and Ukraine continued with President Emmanuel Macron of France speaking to the Russian president, Vladimir V. Putin, by phone on Monday for the second time in four days.

The Kremlin said the two leaders discussed Ukraine and Mr. Putin’s demands for “security guarantees” that would include a legally binding halt on NATO expansion to the east. They agreed to stay in touch by phone and to “work promptly on the possibility of holding an in-person meeting,” the Kremlin said.

The French presidency said in a statement that the phone call was part of “the same logic of de-escalation” as the previous exchanges between the two presidents. An in-person meeting was not ruled out, though nothing was scheduled yet, the statement said.

With the retirement of the German leader Angela Merkel, Mr. Macron has sought to position himself as Europe’s chief voice in international affairs, casting himself as a NATO ally who is independent of Washington and has open channels to U.S. adversaries.

In 2014, after Russia seized Crimea from Ukraine and Russian-backed separatists took control of a slice of eastern Ukraine, France and Germany formed the “Normandy format” talks with Russia and Ukraine — excluding the United States to keep superpower rivalry out of the mix.

The Normandy group helped broker a cease-fire in eastern Ukraine in 2015, and has continued to meet since then — including last week, when diplomats from the four countries gathered in Paris to discuss the latest crisis.

The French presidency said Mr. Macron and Mr. Putin welcomed “positive progress” made by talks under the Normandy format, and that they would continue to “pursue dialogue.”