Ukrainian embassy staffers were aware something was holding up U.S. military aid to their country as early as July 25, the day President Donald Trump pushed Ukrainian President Volodymyr Zelensky to investigate former Vice President Joe Biden and his son, Defense Department official Laura Cooper testified Wednesday evening.

Cooper told the House Intelligence Committees impeachment inquiry into Trump that her staff received emails from Ukrainian officials based in Washington on July 25 asking what was going on with the $391 million in military and security aid. The emails came five hours after the phone call where Trump asked Zelensky to do us a favor by investigating the Bidens business activities in Ukraine.

Previous reports had put early August as the earliest date Ukraine officials were aware that the military aid was being blocked.

U.S. Ambassador to the European Union Gordan Sondland testified earlier on Wednesday that Trump directed a quid pro quo where Zelensky could obtain a White House meeting if he were to announce investigations into possible Ukraine interference in the 2016 U.S. presidential election and Burisma, the gas company that employed Hunter Biden as a board member. Sondland also said he later came to believe that the military aid was part of the quid pro quo.

National Security Council staffer Alexander Vindman first learned that a hold was placed on the aid on July 3. The Office of Management and Budget issued an agency memorandum officially blocking release of the aid on July 18 on Trumps order. This came despite Department of Defense officials telling Congress in February and again in May that Ukraine met conditions to receive the aid. The hold on the aid was first reported publicly by Politico on August 28.

Cooper had previously testified behind closed doors that she first learned that Ukrainians knew that something had snagged delivery of the military aid on Sept. 5. After her testimony was released to the public, her staff approached her with the July 25 emails from the Ukrainian embassy officials.

In desperation to secure the aid, Zelensky and his team had planned to announce investigations into the 2016 election issue and the Bidens on CNN. But on Sept. 9, the intelligence communitys inspector general told the House Intelligence Committee about a whistleblower complaint concerning Trumps comments in his July 25 phonecall with Zelensky.

Three House committees responded by announcing an investigation into the Trump administrations policy toward Ukraine. Two days later, the White House released the aid.