President Joe Biden will sign the $40 billion Ukraine aid bill while he's in Asia, a White House official said.

"The president does intend to sign the bill while he's on the road so that he can sign it expeditiously," national security adviser Jake Sullivan told reporters aboard Air Force One while en route to the region Thursday evening. "The modalities of that are being worked right now so that he can get it and sign it."

The bill, which passed the Senate earlier Thursday with bipartisan support, will need to be flown to the region so that Biden can sign it. The practice of flying bills to presidents for signature dates back to the Truman administration, but this is a first for Biden.

Biden departed for South Korea Thursday and will visit Japan later in the week during his first trip to Asia as president.

-ABC News' Sarah Kolinovsky

U.S. Secretary of State Antony Blinken announced Thursday that he has authorized a 10th drawdown of additional arms and equipment for Ukraine worth $100 million from U.S. Department of Defense inventories.

This brings total U.S. military assistance to Ukraine to approximately $3.9 billion in arms and equipment since Russia invaded Ukraine on Feb. 24.

"The United States is committed to helping Ukraine continue to meet its defense needs and build its future capabilities, as well as to bolster Allies and partners across NATO’s Eastern Flank and the broader region," Blinken said in a statement.

-ABC News' Shannon Crawford

The Senate voted on Thursday to pass an additional $40 billion in new military and economic aid for Ukraine after President Joe Biden called on Congress for more funding.

The bill received bipartisan support, passing with a vote of 86-11.

The House passed the aid package earlier this month, which is now headed to Biden's desk for signing.

"By passing this aid package the Senate can now say to the Ukrainian people help is on the way: real help, significant help, help that could ensure the Ukrainian people are victorious," Majority Leader Chuck Schumer said during his floor remarks before the vote.

-ABC News' Allison Pecorin

U.S. Chairman of the Joint Chiefs of Staff Gen. Mark A. Milley spoke with Chief of Russian General Staff Gen. Valery Gerasimov Thursday, for the first time since the invasion of Ukraine. They last spoke on Feb. 11.

The two discussed several security-related issues of concern and agreed to keep the lines of communication open, according to a readout from the U.S., but the specific details of their conversation were kept private.

The Russian Ministry of Defense said the two sides "discussed issues of mutual interest, including the situation in Ukraine," in a call it said was initiated by the U.S.

-ABC News' Matt Seyler

Jalina Porter, the State Department's deputy spokesperson, is responding to the Russian attack at a Ukraine train station that killed at least 50, saying, "We can no longer be surprised by the Kremlin's repugnant disregard for human life."

Five children were among those killed when Russian rockets struck the station in Kramatorsk in Donetsk Oblast on Friday morning, according to Ukraine's state-owned railway company. At least 100 people were injured, according to Donetsk Oblast Gov. Pavlo Kyrylenko.

Russia has denied involvement in the attack, which occurred as "thousands" of civilians fleeing the Russian invasion were at the train station waiting to be taken to "safer regions of Ukraine," according to Kyrylenko.

"Civilians are killed when they stay in their homes, and they're killed when they try to leave," Porter said. "Actions like these demonstrate why Russia did not belong on the U.N. Human Rights Council, and they also reinforce the U.S. assessment that members of Russian forces are committing war crimes in Ukraine."

Porter declined to say if the department considers the train station attack a war crime, saying, "Assessing individual criminal liability in specific cases is the responsibility of courts, as well as other investigatory bodies. But as the secretary, Secretary [of State Antony] Blinken, has said, 'Those responsible for war crimes and other atrocities committed in Ukraine will be held to account.'"

-ABC News' Conor Finnegan