WASHINGTON, Jan 19 (Reuters) - The U.S. government approved $200 million in additional defensive security assistance to Ukraine in December, a senior State Department official said on Wednesday.

"We are committed to Ukraine’s sovereignty and territorial integrity and will continue to provide Ukraine the support it needs," the official told reporters traveling with U.S. Secretary of State Antony Blinken.

Blinken arrived in Ukraine on Wednesday amid concerns from Kyiv and its Western allies over tens of thousands of Russian troops amassed at the border with Ukraine.

Russia denies planning a new military offensive.

Blinken will meet Ukrainian President Volodymyr Zelenskiy and Foreign Minister Dmytro Kuleba on Wednesday.