President Trump took to Twitter early Saturday morning to take swipes at top Democrats like Nancy Pelosi and Kamala Harris while denouncing the impeachment inquiry in Congress over his relationship with Ukraine.

The President also pledged on Twitter to cover all of the costs of the 10th wedding anniversary celebration held at Camp David for his daughter, Ivanka, and son-in-law, Jared Kushner.

'Had a beautiful dinner last night at Camp David in celebration of the 10th Wedding Anniversary of Ivanka and Jared,' Trump tweeted on Saturday.

'Attended by a small number of family and friends, it could not have been nicer.

President Trump hammered away at his political opponents on Twitter during an early Saturday morning rant that included swipes at California Democrats like House Speaker Nancy Pelosi, House Rep. Adam Schiff, and Senator Kamala Harris

Trump blasted Pelosi (seen above in Washington, DC, on October 17), the House speaker who has ordered an impeachment inquiry against the President

'I can't believe that Nancy Pelosi's District in San Francisco is in such horrible shape that the City itself is in violation of many sanitary & environmental orders, causing it to owe the Federal Government billions of dollars - and all she works on is Impeachment,' Trump tweeted on Saturday

'We should all work together to clean up these hazardous waste and homeless sites before the whole city rots away. Very bad and dangerous conditions, also severely impacting the Pacific Ocean and water supply. Pelosi must work on this mess and turn her District around!'

'Camp David is a special place. Cost of the event will be totally paid for by me!'

In his next tweet, Trump pivoted to the Mueller investigation, which probed whether Russia meddled in the 2016 presidential election.

Former special counsel Robert Mueller's two-year investigation found there wasn't enough evidence to conclude that Trump or anyone associated with his campaign conspired with Russia.

'Not a single American citizen has been charged with anything related to Russian Collusion, not one person,' Trump wrote in his tweet, quoting Fox News host Tucker Carlson.

'It was an illegal Witch Hunt!'

It was announced earlier this week that Attorney General Bill Barr opened a criminal investigation into the origins of the Mueller probe.

Democrats criticized the move, saying the Justice Department was being used as a political weapon by the Trump administration to exact retribution against its critics.

The President also hit out at 'badly failing presidential candidate' Kamala Harris, the senator from California

Trump criticized Harris for pulling out of an event at Benedict College, a historically black school in South Carolina which honored the President on Friday for signing into law a criminal justice reform measure

'This and best unemployment numbers EVER is more than Kamala will EVER be able to do for African Americans!' Trump tweeted

The senator responded to Trump on Twitter, tweeting: 'My whole life I've fought for justice and for the people - something you'd know nothing about. The only part of criminal justice you can claim credit for is the “criminal” part.'

Trump was awarded the Bipartisan Justice Award by Matthew Charles, right, one of the first prisoners released by the First Step Act, during the '2019 Second Step Presidential Justice Forum' at Benedict College on Friday

The President then turned his ire toward Pelosi, the House speaker who made the decision to launch an impeachment inquiry over Trump's efforts to get Ukraine to probe Joe Biden and his son, Hunter.

'I can't believe that Nancy Pelosi's District in San Francisco is in such horrible shape that the City itself is in violation of many sanitary & environmental orders, causing it to owe the Federal Government billions of dollars - and all she works on is Impeachment,' Trump tweeted on Saturday.

'We should all work together to clean up these hazardous waste and homeless sites before the whole city rots away. Very bad and dangerous conditions, also severely impacting the Pacific Ocean and water supply. Pelosi must work on this mess and turn her District around!'

Trump has frequently made mention of American cities that have seen an increase in their homeless population due to the rise in cost of living.

The President has specifically singled out for criticism his hometown of New York City, Los Angeles, and San Francisco.

In July, Trump told Fox News: 'The people living there are living in hell.

'Some of them have mental problems where they don't even know they are living that way.

'In fact, perhaps they like living that way. They can't do that.

'We can't ruin our cities.'

Trump added: 'You have people that work in those cities, they work in office buildings.

Trump began his tweet storm by saying he would pay for the wedding anniversary celebrations of his daughter, Ivanka Trump, and son-in-law Jared Kushner at Camp David

'Had a beautiful dinner last night at Camp David in celebration of the 10th Wedding Anniversary of Ivanka and Jared,' Trump tweeted on Saturday. 'Attended by a small number of family and friends, it could not have been nicer.'

'To get into the building they have to walk through a scene that nobody would have believed possible.'

Back on Twitter, Trump slammed another top Democrat, Rep. Adam Schiff, the chairman of the House Intelligence Committee.

Schiff has taken the lead in the impeachment inquiry against the President.

Trump tweeted: 'The Ukraine investigation is just as Corrupt and Fake as all of the other garbage that went on before it.

'Even Shifty Schiff got caught cheating when he made up what I said on the call!'

Trump is referring to Schiff's opening statement statement from a committee hearing on September 26, when the California Democrat gave a description that he says characterized the July phone call between the President and Ukrainian leader Volodymyr Zelensky.

Back on Twitter, Trump slammed another top Democrat, Rep. Adam Schiff, the chairman of the House Intelligence Committee

Trump tweeted: 'The Ukraine investigation is just as Corrupt and Fake as all of the other garbage that went on before it. Even Shifty Schiff got caught cheating when he made up what I said on the call!'

The President is said to have withheld vital military aid to Ukraine on condition that its government investigate the Bidens and their ties to a Ukrainian gas company where Hunter Biden was a member of the board of directors.

Schiff accused Trump of 'a classic organized crime shake down' by telling Zelensky: 'We've been very good to your country. Very good. No other country has done as much as we have. But you know what, I don't see much reciprocity here. You know what I mean?

'I hear what you want. I have a favor I want from you though. And I'm going to say this only seven times, so you better listen good. I want you to make up dirt on my political opponent, understand?

'Lots of dirt, on this and on that. I'm going to put you in touch with people, and not just any people.'

Trump on Twitter then attacked another Democrat from California, Senator Kamala Harris.

'Badly failing presidential candidate Kamala Harris will not go to a very wonderful largely African American event today because yesterday I recieved [sic] a major award, at the same event, for being able to produce & sign into law major Criminal Justice Reform legislation, which will greatly help the African American community (and all other communities), and which was unable to get done in past administrations despite a tremendous desire for it,' the President tweeted.

'This and best unemployment numbers EVER is more than Kamala will EVER be able to do for African Americans!'

Harris replied to the President, tweeting: 'My whole life I've fought for justice and for the people - something you'd know nothing about. The only part of criminal justice you can claim credit for is the "criminal" part.'

Harris released a statement on Friday saying that she would not attend a forum at Benedict College, a Historically Black College or University that honored Trump for signing into law a criminal justice reform bill.

Passed by overwhelming majorities in Congress, the First Step Act allows inmates who are serving time for selling crack cocaine to ask a judge to reduce their prison sentences.

The law, years in the making, represents an easing of tough, law-and-order minimal sentencing requirements imposed on judges that stemmed from a 1980s drive to clamp down on an epidemic of crack cocaine and other illegal drug use in the United States.

The President is the subject of an impeachment inquiry after he withheld aid from Ukraine until it investigated Joe and Hunter Biden. Trump made the request of his Ukrainian counterpart, Volodymyr Zelensky (pictured above with Trump at the United Nations on September 25)

Trump alleges that then-Vice President Joe Biden (right) pressured Ukraine to fire a prosecutor that was investigating a Ukrainian oil company that named Hunter Biden (left) to a position on its board

The tough enforcement fell heavily on African-Americans and Latinos, even though data pointed to whites constituting the majority of illegal drug users and dealers in the United States.

Harris, who was scheduled to speak at the Columbia, South Carolina-based college on Saturday, pulled out of the event in protest.

'As the only candidate who attended an [Historically Black College or University], I know the importance that these spaces hold for young Black Americans,' said Harris in a statement Friday.

'Today, when it became clear Donald Trump would receive an award after decades of celebrating mass incarceration, pushing the death penalty for innocent Black Americans, rolling back police accountability measures and racist behavior that puts people's lives at risk ... I cannot in good faith be complicit in papering over his record.'

Before she was elected to the Senate, Harris served as attorney general of California and San Francisco's top prosecutor.

She is running for President in a crowded Democratic field, with Joe Biden and Elizabeth Warren having emerged as the two clear frontrunners.

Harris, meanwhile, is lagging behind with support in the single digits, according to public opinion polls.

Trump invited just ten students to his talk at Benedict on Friday, and only seven turned up, according to a spokeswoman.

The President also disputed a report in The Washington Post which claimed that his team is increasingly concerned by the administration's failure to prevent witnesses from coming forward and giving evidence to Congress

'Where's the Whistleblower?' Trump tweeted on Saturday, a reference to the high-level official who filed a complaint about the President's dealings with Ukraine

The President opened the forum on criminal justice reform, touting his support for sweeping reforms that he hopes will help him pick up more votes among African-Americans next year.

But just a handful of students studying there were invited to the event, Mayor of Columbia Stephen Benjamin told CNN.

A number of protesters were also pictured outside the hall as Trump's motorcade arrived, amid reports that students were served lunch inside their dorms, USA Today reports.

Trump on Saturday then posted a video on his Twitter feed praising his administration's efforts to end the opioid crisis.

Finally, the President lashed out at the 'fake' Washington Post for a news story it published which claimed that Trump and his top aides were increasingly worried about their inability to prevent current and former administration officials from giving testimony to Congress in the ongoing impeachment inquiry.

Trump tweeted: 'The Fake Washington Post keeps doing phony stories, with zero sources, that I am concerned with the Impeachment scam.

'I am not because I did nothing wrong.

'It is the other side, including Schiff and his made up story, that are concerned.

'Witch Hunt continues!'

Trump also tweeted: 'Where's the Whistleblower?'

Last month, it was learned that an anonymous government official with access to the White House filed a complaint about Trump's dealings with the Ukraine.

By law, the official is allowed to protect their identity so as to prevent the government from exacting retribution by firing them from their job.