U.S. President Donald Trump listens to a question while speaking to members of the media before boarding Marine One on the South Lawn of the White House in Washington, D.C., U.S., on Thursday, Oct. 3, 2019. Al Drago | Bloomberg | Getty Images

When House Speaker Nancy Pelosi announced an impeachment inquiry into President Donald Trump, the story seemed relatively clear: Reports about a whistleblower complaint raised alarms among Democrats that Trump had solicited a foreign country to investigate former Vice President Joe Biden, his potential political opponent. Just over a week later, the flood of news surrounding Trump, Biden, Congress, Ukraine and China seems almost impossible to stay on top of. Trump has now openly doubled down on his desire for Ukraine to "look into" unsubstantiated allegations of wrongdoing against Biden and his son Hunter — a request he first made in a controversial July 25 call with that country's president, Volodymyr Zelensky. On Thursday, Trump said on the White House lawn that he also wants China to launch a probe into the Bidens and later asserted his "absolute right" to do so. Democrats, predictably, did not approve. As they charge forward with their impeachment inquiry, House Democrats have begun questioning a raft of administration officials. Now, text messages between U.S. diplomats, leaks from closed-door hearings and questions surrounding upcoming trade talks with Beijing have all come into play. Here's what you may have missed:

US officials' texts show Ukraine president's White House visit tied to investigation

Text messages released by the House Intelligence Committee on Thursday showed Kurt Volker, former U.S. special envoy to Ukraine, telling Zelensky aide Andrew Yermak that a visit to Washington would be arranged if the Ukraine leader "convinces trump he will investigate / 'get to the bottom of what happened' in 2016." That assurance was made July 25, just hours before Trump spoke with the newly elected Ukraine president. In that call, Trump asked Zelensky to "do us a favor" and use Attorney General William Barr's help and open a probe of a company involved in the beginnings of the F.B.I. inquiry of Russia's 2016 election interference. "Heard from White House — assuming President Z convinces trump he will investigate / 'get to the bottom of what happened' in 2016, we will nail down date for visit to Washington," Volker texted Yermak, on July 25. The texts also show a Sept. 9 exchange in which Bill Taylor, a senior U.S. diplomat in Ukraine, told Gordon Sondland, the U.S. ambassador to the European Union: "I think it's crazy to withhold security assistance for help with a political campaign." Sondland responded: "Bill, I believe you are incorrect about President Trump's intentions. The President has been crystal clear no quid pro quo's of any kind. The President is trying to evaluate whether Ukraine is truly going to adopt the transparency and reforms that President Zelensky promised during his campaign." Click here to read the texts released by the Intelligence Committee, or scroll down.

Trump called on China to investigate Biden

Trump's call with Ukraine's Zelensky, which spurred Democrats to favor the impeachment inquiry, was initially a private call. But when Trump called on China to investigate the Bidens, he said it on camera to a group of reporters gathered outside the White House. "China should start an investigation into the Bidens, because what happened in China is just about as bad as what happened with Ukraine." Trump said that "I haven't" asked Chinese President Xi Jinping to do so, "but it's certainly something we should start thinking about."

White House plans to slow-walk impeachment push

Trump suggested in a press conference Wednesday that he will "cooperate" with the House's requests in its impeachment probe. But multiple outlets reported shortly after that the White House plans to argue that Pelosi must have the full House vote to formally approve an impeachment inquiry before the Trump responds to lawmakers' requests. A letter making that argument could be sent to Capitol Hill as early as Friday, multiple outlets have reported. Pelosi has said she's under no such obligation to hold a vote before continuing the efforts of the investigation. Without a formal vote, the White House and the Congress might have to take their fight to the courts.

Volker's deposition

Democrats and Republicans came away from Volker's behind-closed-doors testimony to House committees Thursday with starkly different conclusions. Democrats, such as Rep. Eric Swalwell of California, said the deposition included evidence that Trump, through his personal attorney Rudy Giuliani and others, withheld aid to the country and asked Ukraine to look into former Vice President Joe Biden as well as matters related to the 2016 election. Volker, who was named in the whistleblower complaint, abruptly resigned last week. Rep. Jim Jordan, R-Ohio, however, said that nothing Volker said bolstered the case for impeaching Trump.

Trump reportedly ordered ambassador's removal after Giuliani and others complained

The Wall Street Journal reported Thursday that Trump decided to remove U.S. ambassador to Ukraine Marie Yovanovitch, following complaints, including from Giuliani, that she was "obstructing efforts to persuade Kyiv to investigate" Biden. Yovanovitch, who was ousted in the spring, was mentioned in the whistleblower's complaint. "Mr. Giuliani told the Journal that when he mentioned the ambassador to the president this spring, Mr. Trump remembered he had a problem with her earlier and thought she had been dismissed," the newspaper reported. "Mr. Giuliani said he subsequently received a call from a White House official — whom he declined to identify — asking him to list his concerns about the ambassador again."

Trump reportedly brought up Biden in call with China's Xi in June

Ukraine reportedly wasn't the only country whose leader Trump privately asked to investigate the Bidens. CNN reported Thursday that Trump suggested in a June 18 phone call with Chinese President Xi Jinping that China should probe unsubstantiated allegations of wrongdoing against Biden and his son. CNN said that Trump raised the political prospects of both Biden and Sen. Elizabeth Warren, D-Mass., in the call with Xi. Biden and Warren are both widely considered the front-runners in the Democratic presidential primaries. Trump also said "he would remain quiet on Hong Kong protests as trade talks progressed," according to CNN. The president told CNBC's Eamon Javers on Friday morning that his request for China to investigate Biden won't affect high-level trade talks with Beijing, which are scheduled to be held in Washington next week.

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