President Joe Biden's full budget request won't be public until Friday, but a press release issued by the Department of Defense Thursday said it's expected to contain $715 billion in funding for the department.

Both Defense Secretary Lloyd Austin and Chairman of the Joint Chiefs of Staff Gen. Mark A. Milley told lawmakers the funding was sufficient for the department's needs and suited its priorities.

"This budget provides us the ability to create the right mix of capabilities to defend this nation and to deter any aggressors," Austin said during testimony before the House Appropriations Committee's subcommittee on defense.

Austin said the budget includes investments in hypersonic weapons, artificial intelligence, microelectronics, 5G technology, cyber capabilities, shipbuilding and nuclear modernization -- as well as climate change mitigation and preparation for a future pandemic.

The budget also includes funding to resist Russian cyberattacks, counter threats from countries like North Korea and Iran and maintain troop presence in the Middle East and South Asia.

"It strikes an appropriate balance between preserving present readiness and future modernization," Milley said, adding that it is "biased towards [the] future operating environment."

According to Milley, it's particularly important for the United States fund modernization and advanced technologies like hypersonics and artificial intelligence.

He cautioned that China is "investing heavily" in high-tech defense capabilities, and the U.S. needs to do so as well.

Milley also told lawmakers the National Defense Strategy produced under former President Donald Trump's administration "needs to be updated," though some major pieces of strategy are the same.

The $715 billion ask is slightly lower than the fiscal 2021 budget of $740 billion that passed in December despite a veto from Trump.

He objected in part because he'd asked lawmakers to include language repeal of Section 230 of the Communication Decency Act, which protects technology companies from being liable for content published on their platforms.

Also Thursday, Austin told lawmakers that the drawdown of troops from Afghanistan is "proceeding on pace, indeed slightly ahead of it."