Russian President Vladimir Putin announced that Russia would undertake a special military operation in the Donbas region in eastern Ukraine in a speech on Russian state TV early Thursday morning.

Putin said the operation is aimed at what he called the "demilitarization" and "denazification" of Ukraine.

Putin said Russia’s plans did not include occupying Ukraine, but he called on Ukrainian soldiers to lay down their arms and go home.

He warned outside countries not to interfere.

The U.S., France and other members of the United Nations Security Council are working on a draft resolution to condemn Russia during its late-night session Wednesday, according to France's permanent representative to the U.N.

In somewhat of a rarity, U.N. Secretary-General Antonio Guterres addressed the chamber, speaking to the urgency of the meeting.

Looking directly into the camera ahead of him, Guterres addressed Russian President Vladimir Putin.

"If indeed an operation is being prepared, I have only one thing to say from the bottom of my heart: President Putin, stop your troops from attacking Ukraine. Give peace a chance. Too many people have already died," he said.

Before the meeting, Guterres chatted with Russian Ambassador Vasily Nebenzya, who also talked with China's envoy Zhang Jun.

It's unclear if the resolution will get a vote during the emergency session. But when it comes up, it will likely be denied by Russia and its veto power.

In 2014, after Russia annexed Crimea from Ukraine, a U.S. resolution declaring the action invalid was denied by Russia's veto, while China abstained. The U.S. then brought the resolution to the U.N. General Assembly, where resolutions are non-binding but every member has a vote. It passed with about 100 votes in favor.

-ABC News' Conor Finnegan

Russia has issued a series of NOTAMs, or Notice to Air Missions, in northeastern Ukraine as a warning to civilian aircraft in the area.

There are 12 NOTAMs from Russia providing coordinates that map in northeastern Ukraine. They include warnings to airports in Kyiv, Lviv, Dnipro and Odesa and say they are "due to potential hazard for civil aviation."

These alerts are a warning from Russia to flights entering these areas that they do so at their own risk.

-ABC News' Christine Theodorou

In another indication that an invasion of Ukraine may be very close to taking place, Russian military leaders have gone to their command center, and cyberattacks are underway, according to a U.S. official.

Gen. Mark Milley, chairman of the Joint Chiefs of Staff, believes any invasion has to happen during the night, the official said.

-ABC News’ Chief Global Affairs Correspondent Martha Raddatz

In response to a plea on Twitter from a Ukrainian official, SpaceX CEO Elon Musk said Saturday that his high-speed internet service Starlink is now active in Ukraine.

"More terminals en route," he tweeted in a reply to Mykhailo Fedorov, Ukraine's vice prime minister and minister of digital transformation.

Earlier Saturday, Fedorov appealed directly to Musk and asked him to provide Ukraine with Starlink stations.

The terminals are small, portable satellite dishes on Earth that connect directly to Starlink satellites in space -- providing high-speed internet to rural and hard-to-reach locations. This is especially important for areas that have already lost access and could potentially help them avoid cyberattacks.

-ABC News' Gio Benitez