President Trump claimed Thursday that Senate Minority Leader Chuck Schumer is 'groveling,' but fellow Democratic leader Nancy Pelosi is refusing appeals to end to the government shutdown, because she's beholden to the radical left.

Trump mocked the Senate minority leader and claimed the left-flank of the Democratic Party has become unglued in morning tweets.

He said in a national security speech later in the day that Pelosi will not let lawmakers work with him to come to a border security solution.

'The party has been hijacked by the open borders fringe within the party, the radical left, becoming the radical Democrats,' he said. 'Hopefully Democrat lawmakers will step forward to do what is right for our country, and what's right for our country is border security at the strongest level.'

President Trump claimed Thursday that Senate Minority Leader Chuck Schumer is 'groveling,' but fellow Democratic leader Nancy Pelosi is refusing appeals to end to the government shutdown, because she's beholden to the radical left

He added: 'Stop human hijacking, stop drugs, stop gangs, stop criminals. That's what we're gonna do. That was my pledge, and that's what we're going to do.'

Until then, the federal government will remain shutdown because congressional Democrats refuse to approve border security, he said.

'We're going to have border security. It's going to be tight. It's going to be strong. We're going to let people into our country gladly, but they're going to come in legally,' he contended.

The president brought up the situation at the southern border during a speech on his Missile Defense Review at the Pentagon early Thursday afternoon.

'I would like to briefly address another matter of critical national security, the humanitarian and security crisis at our southern border,' he said leading into his daily pitch for a border wall. 'Without a strong border, America's defenseless, vulnerable and unprotected.'

He thanked the military for 'helping us out during the big caravan period' as he made reference to another group of Central American migrants that has reportedly formed.

'Thousands and thousands of people. We don't know where they're from, who they are, nothing,' he asserted. 'We need strong borders. We need strong barriers and walls. Nothing else is going to work. Everyone knows it. Everybody's saying it now. Just a question of time.'

'While many Democrats in the House and the Senate would like to make a deal, Speaker Pelosi will not let them negotiate,' Trump said of the status of the shutdown

Yesterday, the No. 2 Democrat in the House, Rep. Steny Hoyer, admitted that walls 'obviously' work sometimes and that the barrier is not 'immoral' on its face. Rep. Katie Hill, a California Democrat, has also said a physical barrier like Trump wants could be effective.

'While many Democrats in the House and the Senate would like to make a deal, Speaker Pelosi will not let them negotiate,' Trump said of the status of the shutdown. 'The part has been hijacked by the open borders fringe.'

Trump said earlier in a tweet that had no apparent connection to any news story, but appeared to be about immigration: 'The Left has become totally unhinged. They no longer care what is Right for our Countrty!'

The president misspelled the word 'country' in the message. He did not send out a corrected version of the tweet.

He went on to bash Schumer, the Senate Democratic leader, in a tweet for 'groveling' for another meeting at the White House.

Trump walked out of their last one, and hasn't spoke to the party leader since.

Schumer offered to come back to the table as he spoke to reporters on Tuesday, if Trump will have him.

'I’ll meet with him anytime he wants. As you know, the last I spoke with him was when he walked out, threw a temper tantrum and walked out, so we haven’t heard from him since then.'

Trump said earlier in a tweet that had no apparent connection to any news story, but appeared to be about immigration: 'The Left has become totally unhinged. They no longer care what is Right for our Countrty!'

Trump last week harangued newly-elected liberals as 'crazy' while speaking to reporters outside the White House.

He seemed to be refer to freshman lawmaker Alexandra Ocasio-Cortez, a self-proclaimed democratic socialist, as he slammed 'young people' in the party who want to abolish Immigration and Customs Enforcement.

'They've been taken over by a group of young people who, frankly, in some cases -- I've been watching -- I actually think they're crazy,' Trump said before a Jan. 10 departure in Marine One.

Speaking about Democrats, he said, 'They've been taken over by a group that is so far left. I really don't think they care about crime.

'And, you know, sadly, they're viewing this as the beginning of the 2020 presidential race, and that's okay with me. But they have been taken over by a group of people that don't care about gangs. They don't care about human trafficking and drugs,' he claimed.

'They don't care about anything. I'll tell you what -- they have gone crazy.'

Trump has equated Ocasio-Cortez and a handful of other elected Democrats' position on totally eliminating the United States' deportation force with the party at large.

He has repeatedly claimed that the party wants 'open borders' and crime and that's why they are defying his request for a border wall.

After his tweet about the left on Wednesday morning, he retweeted a supporter who claimed that Democrats are being 'eaten alive' by Trump and his base.

'They care more about illegal immigrants than they do for American citizens! Look no further than CA re-directing money away from US citizens to illegal immigrants. Thank you for putting America 1st Mr. President,' the Twitter user said.

The argument is part of a broader fight the president is waging right now against Democrats who will not give him the $5.7 billion he's demanding for his border wall.

He has overseen a partial government shutdown for nearly a month over their refusal to approve the funds.