WASHINGTON - Democrats in the U.S. House of Representatives announced formal impeachment charges against President Donald Trump on Tuesday, a historic move that set the stage for a divisive trial in the Republican-led Senate ahead of the 2020 elections.The two formal charges, or articles of impeachment, accuse Trump of "betraying" the country by abusing power in an effort to pressure Ukraine to probe a political rival and then obstructing Congress' investigation into the scandal. The Democratic-controlled House is almost certain to vote to impeach the president. It could take up the matter next week. A trial would then be held in the Senate, likely in January. No Republican in either the House or Senate has come out in favor of Trump's removal from office.House Judiciary Committee Chairman Jerrold Nadler told reporters that Democrats had to take action because Trump had endangered the U.S. Constitution, undermined the integrity of the 2020 election and jeopardized national security."No one, not even the president, is above the law," Nadler said at a news conference to announce the formal impeachment charges. He was joined by House Speaker Nancy Pelosi and other Democratic leaders involved in the impeachment probe."Our elections are a cornerstone of democracy. ... The integrity of our next election is at risk from a president who has already sought foreign interference in the 2016 and 2020 elections," Nadler said.Trump has denied wrongdoing and calls the inquiry a hoax.The White House, which has refused to participate in the hearings in the House because it says the process is unfair, accused Democrats of engaging in a "baseless and partisan" attempt to undo the results of the 2016 election."The President will address these false charges in the Senate and expects to be fully exonerated, because he did nothing wrong," White House spokeswoman Stephanie Grisham said in a statement. In an interview with Fox News, Grisham, asked whether Trump would testify, said she did not know.After the articles of impeachment were announced, Trump tweeted "WITCH HUNT!" Earlier, he attacked the impeachment effort, tweeting that to impeach a president when the country has such a strong economy "and most importantly, who has done NOTHING wrong, is sheer Political Madness!"He is the fourth U.S. president to face impeachment.Democratic President Bill Clinton was impeached in 1998 for lying about a sexual relationship he had with a White House intern, but he was acquitted in the Senate. Republican President Richard Nixon resigned in 1974 before he was impeached over his involvement in the Watergate scandal. Democratic President Andrew Johnson was impeached in 1868 but not convicted in the Senate.'OBSTRUCTION AND STALEMATE'Democrats have moved rapidly since launching their inquiry in late September after a whistleblower complaint about a July 25 telephone call in which Trump sought help from Ukrainian President Volodymyr Zelenskiy to investigate former Vice President Joe Biden, a leading contender in the Democratic race to challenge Trump in next November's election.The abuse of power charge accuses Trump of using nearly $400 million in U.S. security aid and a possible White House meeting with his Ukrainian counterpart to solicit Ukraine to publicly announce the investigations of Biden and a debunked theory that Ukraine, not Russia, interfered in the 2016 U.S. election.The obstruction charge accuses the president of defying and impeding the House's efforts to investigate the scandal, adding that Trump would remain a threat to the U.S. Constitution if he remained in office.Representative Adam Schiff, the Democrat who spearheaded the investigation in the House Intelligence Committee, said impeachment was an extraordinary remedy but that Trump had given Democrats no choice."The evidence of the president's misconduct is overwhelming and uncontested," Schiff said.Republicans argue Trump did nothing improper in his call with Zelenskiy and say there is no direct evidence he withheld aid or a White House meeting in exchange for a favor.Senate Majority Leader Mitch McConnell complained that the impeachment process had delayed work on other matters."Obstruction and stalemate have brought us to the 11th hour. I hope ... that both chambers will be able to set aside Democrats' impeachment parade long enough to get the people's business finally finished," he said on the Senate floor.Democrats sought to counter the argument that impeachment was being done at the expense of passing major legislation.Democratic Representative Tom Malinowski pointed to upcoming votes in the House on a new trade deal between the United States, Canada and Mexico, two healthcare-related bills, legislation to fund the government through next September, in addition to impeachment, as examples of movement on key issues.The impeachment battle has divided Americans and raised the heat in an already polarized Congress. Top Democrats initially had been reluctant to pursue Trump's impeachment out of concerns doing so could hurt the party in 2020.Republicans warned that Democrats were setting a dangerous precedent."Future Congresses will inevitably make impeachment a political tool to be used anytime a President of the opposing party occupies the White House," Republican Senator Lindsey Graham said in a statement.The House Judiciary panel will vote on Thursday on whether to send the formal charges to the full House for a vote.House Majority Leader Steny Hoyer, the Democrat in charge of scheduling debates on the House floor, told reporters on Tuesday: "I don't want to get ahead of the (Judiciary) Committee, but potentially" the two articles of impeachment will be debated on the House floor next week.