WASHINGTON (Reuters) - The House of Representatives is determined to obtain transcripts of telephone conversations between President Donald Trump and his Russian counterpart Vladimir Putin and leaders of other nations, the chairman of the House Intelligence Committee said on Tuesday, while Trump called his investigation the biggest political fraud in US history.

Schiff recalled fears that Trump might have endangered US national security in a way that he believed could benefit him personally in his campaign.

US House of Representatives Speaker Nancy Pelosi said public opinion has changed and now supports the investigation into the trial of a German parliamentarian after disclosing additional information about Trump's phone call with Ukraine's president.

She noted that the House Intelligence Committee will take the appropriate time in pursuing all the facts of the case.

"It is a sad period for our country. There is nothing to be happy about," Pelosi said. "We should mourn and pray, but we will continue to pursue the facts to decide whether the president violated the US Constitution, and I think he did."

Pelosi played down accusations that she was pursuing a political adventure, arguing that the US president should not disrupt the presidential oath because it undermines national security and the integrity of elections, a key pillar of her country's democracy.

Democrats seek transcripts of Trump phone talks with Putin (Anatolia)

Scam
In a video posted on Twitter, President Trump described the Democrats' efforts to prosecute him as the biggest fraud in US policy history.

Trump, facing inquiries in the House of Representatives, called on Republicans to confront the Democrats and prevent them from achieving their goals.

Trump also said he had the right to meet the anonymous informant, who complained about the president's behavior with Ukraine, which has escalated into an investigation into his question last week.

"Like every American, I deserve an interview with those who accused me, especially when this indictment, called the" information trainer, "reviews a perfect conversation with a foreign leader in an inaccurate and completely false manner," Trump said on his Twitter page.

In a series of tweets, the US president asked to interview all sources who had been informed of the information leaker's complaint and to interview Adam Schiff to uncover fraud and betrayal.

"Was this person spying on the American president? There have to be big consequences!"

Trump and Pelosi in an earlier meeting at the White House (French)

Achieve and accountability
The comments come days after the House of Representatives, which is controlled by the Democrats, opened an investigation to question Trump in preparation for his removal, on charges of abuse of power and betraying the presidential oath.

The White House released Trump's call with his Ukrainian counterpart Volodymyr Zelinsky in July, demanding the opening of a corruption case in Kiev against potential Democratic presidential rival Joe Biden and his son Hunter, on suspicion of a Ukrainian gas company. The latter has been working for years.

Meanwhile, a CBS poll on Sunday showed that 55 percent of Americans support efforts to prosecute and oust the president.

The polarization and political divide between Republican and Democratic supporters has emerged, according to the poll, with most Democrats seeing Trump's handling of issues with Ukraine illegal and deserving of isolation.

Most Republicans considered Trump's actions to be correct, and even if not, they are still legal.