Donald Trump has falsely claimed he has the “absolute right” to ask foreign countries to investigate his opponents over alleged corruption.

“As the president of the United States, I have an absolute right, perhaps even a duty, to investigate, or have investigated, CORRUPTION, and that would include asking, or suggesting, other countries to help us out!” Mr Trump said, in a tweet posted during the early hours of Friday.

The controversial leader’s comment comes after Democrats accused him of illegally pressuring Ukraine to probe unsubstantiated allegations about the Biden family.

Democrats announced plans to impeach the president after a whistleblower complained about a 25 July call between Mr Trump and the leader of Ukraine.

In a summary of the call Mr Trump suggested Ukraine should investigate Joe Biden’s son Hunter, who served on the board of a Ukrainian company.

Everyone Trump has fired or forced out Show all 13 1 /13 Everyone Trump has fired or forced out Everyone Trump has fired or forced out John Bolton Trump claimed to have fired Bolton, his national security adviser, while Bolton claimed he offered to resign. An anonymous White House source that Bolton's departure came as a result of the national security adviser working too independently of the president AFP/Getty Everyone Trump has fired or forced out Anthony Scaramucci Scaramucci lasted only six days in his role as Trump's communications director before being fired by John Kelly, the incoming chief of staff Getty Everyone Trump has fired or forced out Rick Perry Rick Perry announced his resignation just as he became embroiled in the president's impeachment scandal. The White House said Mr Perry was asked by Donald Trump to work with Rudy GIuliani in regards to Ukraine. AP Everyone Trump has fired or forced out Rex Tillerson Tillerson, Trump's first secretary of state, was fired after a series of clashes with the president over policy Getty Everyone Trump has fired or forced out James Mattis Mattis served as secretary of defense from the beginning of Trump's administration until retiring on 1 January 2019. However, the president later claimed that he had "essentially fired" Mattis Getty Everyone Trump has fired or forced out James Comey Comey was fired as director of the FBI early in Trump's presidency after serving in the role for four years prior. His dismissal is widely thought to have been related to the Russia investigation Getty Everyone Trump has fired or forced out Reince Priebus Priebus, Trump's first chief of staff, was forced out after six tumultuous months AFP/Getty Everyone Trump has fired or forced out David Shulkin Veterans affairs secretary Shulkin claims that he was fired, the White House claims that he resigned Getty Everyone Trump has fired or forced out John Kelly Kelly, Trump's second chief of staff, was forced out after 17 months in office. His departure was a confused affair though it is clear that Trump wanted Kelly out AFP/Getty Everyone Trump has fired or forced out Michael Flynn Flynn lasted 24 days as Trump's national security adviser before being fired for lying to the FBI Getty Everyone Trump has fired or forced out Lee Cisna Cisna served as director of citizen and immigration services between October 2017 and June 2019 before being asked to resign amid a major personnel change in the department of homeland security Everyone Trump has fired or forced out Madeline Westerhout Westerhout served as Trump's personal assistant after leaking private information about his family AFP/Getty Everyone Trump has fired or forced out Mira Ricardel Ricardel was forced out of her role as Deputy National Security Advisor after first lady Melania Trump publicly called for her to be fired

The president also delayed around $250m (£202m) in military aid for Ukraine.

Mr Trump has denied any wrongdoing but on Thursday also called on China and Ukraine to investigate the Bidens.

“[Ukraine] should investigate the Bidens,” Mr Trump told journalists.

“And by the way, likewise, China should start an investigation into the Bidens.”

Joe Biden, the former vice-president, is one of the Democratic frontrunners for 2020. A Ukrainian investigation into a company called Burisma, where Hunter Biden served on the board, no evidence of criminal wrongdoing by its owner.

The investigation was subsequently closed, but on Friday, Ukraine's current chief prosecutor announced that it was reviewing the closure of criminal investigations.

A series of text messages, handed over by one diplomat to a congressional investigative committees, reveal that envoys were pressuring Ukraine to publicly announce an investigation.

Under the Federal Election Campaign Act it is illegal in the US to accept foreign aid to interfere with elections in the US. In an apparent warning to the president, Ellen Weintraub, head of the Federal Election Commission, retweeted on Thursday a post she first published in June about receiving foreign help in elections.

“Let me make something 100 per cent clear to the American public and anyone running for public office: It is illegal for any person to solicit, accept, or receive anything of value from a foreign national in connection with a U.S. election,” she said.

“This is not a novel concept.”

The president is not exempt from the scope of the law.

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