KYIV/WASHINGTON, Jan 11 (Reuters) - Ukraine and the United States remain united in seeking to defuse a standoff with Moscow through diplomacy and are working closely to deter Russian aggression, Ukrainian Foreign Minister Dmytro Kuleba said after speaking to his U.S. counterpart. Kuleba spoke to Secretary of State Antony Blinken a day after the United States urged Russia at talks in Geneva to pull back an estimated 100,000 troops from near Ukraine"s borders. Russia staged live-fireexercises in areas near Ukraine on Tuesday, casting doubts on Russia"s willingness to ease the tensions as talks continue. Members of the NATO alliance will meet with Russian officials in Brussels on Wednesday and more talks are planned at the Organisation for Security and Cooperation in Europe (OSCE) in Vienna on Thursday. "Amid the week of diplomatic contacts with Russia, Ukraine and the U.S. remain united in seeking de-escalation through diplomacy and strength. We keep working closely together to deter further Russian aggression," Kuleba tweeted. U.S. State Department spokesperson Ned Price said Blinken assured Kuleba that no substantive discussions about Ukraine would take place without Ukraine. "He reiterated that if Russia chooses the path of further conflict, the United States and our Allies and partners are prepared to impose enormous costs on Russia’s economy, to reinforce NATO’s presence in frontline Allied states, and to increase defensive assistance to Ukraine," Price said in a statement.