US Republican Senator John McCain claimed that the United States' unwillingness to send weapons to the Ukrainian army is a "great shame", leading to Ukrainian military casualties.

WASHINGTON, December 6 (Sputnik) — The United States' unwillingness to send weapons to the Ukrainian army is a "great shame", leading to Ukrainian military casualties, US Republican Senator John McCain told RIA Novosti.

"The great shame and dishonour of America is the fact that we haven't given them weapons to defend themselves," McCain said.

The 78-year-old senator added that Washington is "directly responsible for the deaths of over 400 brave men who have given their lives already," meaning casualties among the Ukrainian government forces.

McCain also confirmed that the US Senate would return to the issue of military aid for Ukraine in January.

Addressing the US Congress in September, Ukraine’s President Petro Poroshenko requested both lethal and non-lethal military assistance to the country's armed forces. The White House has so far refused to provide weapons, limiting the aid to non-lethal supplies.

In April Kiev launched a military operation against independence supporters in the eastern Ukrainian regions of Donetsk and Luhansk, which has killed over 4,300 people.

The warring sides reached a ceasefire agreement in September, but have since accused each other of violating the truce.