In Kiev, Blinken will meet with Ukrainian President Volodymyr Zelensky and Foreign Minister Dmytro Kuleba "to strengthen the US commitment to Ukraine's sovereignty and territorial integrity," according to Foreign Ministry spokesman Ned Price.
In Berlin, Blinken will "discuss recent diplomatic engagements with Russia and joint efforts to deter further Russian aggression against Ukraine, including the readiness of allies and partners to impose massive consequences on Russia and serious economic costs."
Blinken will meet with German Foreign Minister Annalena Baerbock, followed by a meeting with the Transatlantic Quad, which also includes Britain and France, according to Price.
Blinken's visit follows last week's diplomatic negotiations between the West and Russian officials, which ended without a commitment from Russia that it would de-escalate and withdraw the tens of thousands of troops it had gathered on the Ukrainian border, prompting a senior US official to warn that "The drumming of the war sounded loud."
The United States has assured Ukraine of its commitment to the country, amid new warning signs and US intelligence services suggesting that Russia is preparing for a Ukraine invasion.
The United States has information that Russia has put a group of operators in advance to carry out a false flag operation in eastern Ukraine in an attempt to create a pretext for an invasion, as CNN first reported and the White House later confirmed. These operators are "trained in civil warfare and in using explosives to carry out acts of sabotage against Russia's own proxy forces," White House Press Secretary Jen Psaki said on Friday.
Russia has also begun evacuating its embassy in the Ukrainian capital, potentially in preparation for a looming conflict, The New York Times reported. Russia has rejected the report, saying the embassy is functioning normally.
Blinken will be the latest U.S. official to visit Zelensky, after CIA Director Bill Burns met with the Ukrainian leader last week and a delegation of U.S. senators met with Zelensky on Monday.
This story has been updated.