Two people familiar with the request stated Friday that the Biden administration is asking Congress for $6.4 billion to fund an initial U.S. response to Russia’s invasion in Ukraine. The majority of the money will be used for humanitarian assistance, and military operations in the region.

One person said that the largest amounts of money would go to the Defense and State departments and for U.S. Agency for International Development. This agency distributes civilian foreign assistance. The Treasury and Commerce departments would receive smaller amounts. Their chief roles in the Ukraine crisis include applying sanctions against Russia, its financial institutions and its state-owned companies and leaders.

This request was made by the White House and other administration officials to congressional aides during a conference call. It provides an early glimpse at the potential costs American taxpayers might face as a result Russia’s attack against its western neighbor. As Russian forces attacked Kyiv, Ukraine’s capital, those assaults took place on Friday.

The $6.4 billion figure was lower than the $10 billion Sen. Chris Coons, D.Del., had told reporters he expected earlier Friday.

The two people who described the call said that it was clear that the $6.4billion number could be changed based on the events in Ukraine. Coons, who chairs the Senate Appropriations Subcommittee that monitors foreign aid and State Department spendings, had referred to his figure as “an initial guess.”

According to one person who was familiar with Friday’s conversation, the Defense money was used primarily to support NATO countries in Russia’s west. Because the individuals were not authorized to speak publicly about it, the phone conversation between congressional and administration officials was kept confidential.

Coons stated that he expected the administration request would cover the cost of aiding millions of Ukrainian refugees fleeing to Poland and other NATO countries, as well as supporting their armed forces.

He suggested that U.S. assistance to Ukraine could continue if it falls to Russian forces. He said there was “strong enthusiasm” to provide money to resupply, train, and “any other covert or overt support necessary and appropriate to the Ukrainian resistance.”

Coons stated that the money would also be used to monitor and enforce U.S. sanctions on Russia, and to pay Pentagon bills for deployment of the additional 7,000 American troops that President Joe Biden ordered be sent in Europe.

Coons stated that he expects there to be a supplemental demand well over $10 billion. He called it “an initial guess”.

Republican legislators would be likely to support money to Ukraine and counter Russia. Coons stated that he believes the request will get strong bipartisan support. Spokespersons of the leading Republicans didn’t immediately respond to requests for comment.

After returning from a lengthy trip to Germany and Poland, Coons spoke. He and other members discussed the crisis with European leaders.

Biden will likely address the invasion in his State of the Union address to Congress Tuesday.

After a recess, lawmakers will focus their attention next week on bipartisan legislation funding federal agencies for the remainder of this year. Leaders expect to approve the roughly $1.5 trillion measure before March 11, when money temporarily funding government will run out.

Initial confusion surrounded whether or not the Ukraine money would be included in the broader budget legislation. It was also unclear how fast it would move, and whether or not lawmakers would try to attach additional U.S. sanction against Russia.

A congressional leadership aide said that Democrats are considering including Ukraine assistance and additional money for COVID-19 relief as part of the government-wide budget bill. They spoke under anonymity because they weren’t authorized to speak publicly about the matter.

Rep. Barbara Lee (D-Calif.), who heads the House Appropriations Subcommittee that oversees foreign aid oversight, stated earlier this week that the administration expected to require at least $1billion for humanitarian assistance and an additional $1billion in loan guarantees for economic support.

As lawmakers try to finish up their budget work, officials from the administration have already told Congress they would like to add $30 billion to fight the COVID-19 pandemic. This would cover vaccines, testing, and care for the uninsured.

This proposal has been met with strong opposition by the GOP. It is likely to face a difficult climb to survival. Republicans argue that the administration should use funds left over from multi-trillion-dollar COVID-19 relief measures.