
WASHINGTON — The Russian military buildup at the Ukraine border and in Crimea could provide enough forces for a limited military incursion, the C.I.A. director, William J. Burns, told senators on Wednesday as he and other senior officials outlined a range of threats facing the United States.
Russia could simply be sending a signal to the United States or trying to intimidate the Ukrainian government, but it had the abilities in place to do more, Mr. Burns told the Senate Intelligence Committee.
“That buildup has reached the point that it could provide the basis for a limited military incursion, as well,” Mr. Burns said. “It is something not only the United States but our allies have to take very seriously.”
Mr. Burns testified alongside Avril D. Haines, the director of national intelligence, and other officials about an array of threats from global powers like Russia and China as well as challenges that have been less of a focus of intelligence agencies in the past, including domestic extremism and climate change.
annual threat assessment report, released Tuesday ahead of the hearing, the intelligence community said that China’s push for global power posed a threat to the United States through its aggression in its region, its expansion of its surveillance abilities and its attempts to dominate technological advances.
Russia has also pushed for a sphere of influence that includes countries that were part of the Soviet Union, like Ukraine, the report said.
Both China and Russia, however, wanted to avoid direct confrontation with the United States, the report said.
Mr. Burns said the Russian actions have prompted internal briefings as well as consultations with allies. President Biden’s call on Tuesday to President Vladimir V. Putin of Russia was intended to “register very clearly the seriousness of our concern,” Mr. Burns said.
The United States has been tracking the Russian troops for some time, at least since late March. American officials have said privately that the Russians have done little to hide their troop buildup, unlike in 2014 when they first attacked Ukraine. That has convinced some, but not all, officials briefed on the intelligence that the Russian activities may be mostly for show.
penetrated nine federal agencies, and another by China that compromised Microsoft Exchange servers. The Biden administration is expected to respond to the Russian hacking soon, most likely with sanctions and other measures.
Ms. Haines said Russia used hackings to sow discord and threaten the United States and its allies. “Russia is becoming increasingly adept at leveraging its technological prowess to develop asymmetric options in both the military and cyberspheres in order to give itself the ability to push back and force the United States to accommodate its interests,” she said.
Lawmakers also raised the issue of a series of mysterious episodes that have injured diplomats and C.I.A. officers overseas. Some former officials believe Russia is behind the episodes, which they have called attacks.
Mr. Burns said he was working with his colleagues to ensure better medical care for C.I.A. officers. He also said he was working to “get to the bottom of the question of what caused these incidents and who might have been responsible.”
Questions on China dominated the earlier Senate confirmation hearings for Ms. Haines and Mr. Burns, and lawmakers again pressed on Wednesday for assessments on China and its efforts to steal American technology. Ms. Haines outlined how China uses technological might, economic influence and other levers of power to intimidate its neighbors.
“China is employing a comprehensive approach to demonstrate its growing strength and compel regional neighbors to acquiesce to Beijing’s preferences,” she told senators.