Rev Franklin Graham has spoken out against those who have supported an impeachment inquiry against US President Donald Trump.

The evangelist tweeted on Wednesday that it was a 'day of shame for America' as the first public hearing in the impeachment inquiry has got under way in Washington.

He also urged Christians to pray for the nation's leader.

It's a day of shame for America. The media is calling the Democratic-led impeachment inquiry "historic;" and it is—historically shameful. That our politicians would bring this kind of harm to our country with the world watching is unbelievable. 1/2

— Franklin Graham (@Franklin_Graham) November 13, 2019

As Christians, as those who follow and trust in the Lord Jesus Christ, let us pray throughout the day and all of these proceedings. Pray for our nation, pray for our leaders, and pray for @POTUS @realDonaldTrump. 2/2

— Franklin Graham (@Franklin_Graham) November 13, 2019

 The president thanked Rev Graham for his support. 

Thank you @FranklinGraham. It is a time of "shame" for our Country. The Democrats know what they are doing is wrong! https://t.co/O32ybh04vc

— Donald J. Trump (@realDonaldTrump) November 14, 2019

On Wednesday Mr Trump said he was "too busy" doing the people's business to watch the impeachment hearings that imperil his presidency.

The top U.S. diplomat in Ukraine William Taylor and career Foreign Service officer George Kent, center, testify before the House Intelligence Committee on Capitol Hill in Washington, Wednesday, Nov. 13, 2019, during the first public impeachment hearings of President Donald Trump's efforts to tie U.S. aid for Ukraine to investigations of his political opponents.

But even as Mr Trump tried to suggest he was above the fray, the president tweeted two dozen times before noon laying out his grievances about the process playing out on the opposite end of Pennsylvania Avenue.

"It's a witch hunt, it's a hoax, I'm too busy to watch it," Mr Trump told reporters.

During the hearing on Wednesday a senior diplomat told House Intelligence Committee the US president was overheard asking about "the investigations" he wanted Ukraine to pursue that are central to the impeachment inquiry.

Top U.S. diplomat in Ukraine William Taylor testifies before the House Intelligence Committee on Capitol Hill in Washington, Wednesday, Nov. 13, 2019, during the first public impeachment hearing of President Donald Trump's efforts to tie U.S. aid for Ukraine to investigations of his political opponents.

Mr Taylor said his staff recently told him they overheard Mr Trump speaking on the phone to another diplomat, Ambassador Gordon Sondland, at a restaurant the day after Mr Trump's July phone call with the new leader of Ukraine.

The staff explained that Mr Sondland had called the president and they could hear Mr Trump on the phone asking about "the investigations", he said.

The ambassador told the president the Ukrainians were ready to move forward, Mr Taylor testified at the proceedings, which were broadcast live, and on social media, from a packed hearing room on Capitol Hill.

President Donald Trump and Turkish President Recep Tayyip Erdogan meet in the Oval Office with Republican senators at the White House Wednesday, Nov. 13, 2019, in Washington.

Mr Trump was asked about the phone call during a news conference with Turkish president Recep Tayyip Erdogan.

"I know nothing about that," he said, adding that he "did not recall" the conversation.

The inquiry was launched after an anonymous whistle-blowers' complaint that Mr Trump, in the July phone call, pressured Ukrainian president Volodymyr Zelensky to investigate Democratic foe Joe Biden and Biden's son - all while the US was holding up US military aid.

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