The government is still shut down. Here are 5 key events to watch on the 19th ...

White House press secretary Sarah Sanders was just asked why the President didn't declare a national emergency despite describing a "crisis" at the border. She said it's still a possibility

"Something that’s still on the table," she said. "The best solution is to work with Congress to get this done because you can close a lot of the loop holes, fund border security fully and that’s what we’re hopeful to do.”

Congressional leaders will go to the White House at 3 p.m. ET today to meet with President Trump on the government shutdown.

Since parts of the government shut down last month, the Trump administration officials and lawmakers have met multiple times, but they haven't reached a deal. Vice President Mike Pence led two days of talks over the weekend, which did not result in a breakthrough.

Today's White House meeting comes a day after the President made a televised appeal to Americans for his long-promised border wall, offering familiar warnings but scant detail on how he will negotiate an end to the shutdown.

Tomorrow, Trump is will visit the US-Mexico border to "meet with those on the front lines of the national security and humanitarian crisis," White House press secretary Sarah Sanders announced earlier this week on Twitter.

It's the 19th day of the government shutdown, and talks are still static.

The bottom line positions of the leaders from both sides don’t just remain unchanged — they appear to be further entrenched.

Still, leaders and lawmakers will meet today on the shutdown. Here are the key events we're watching:

Some members of Congress are refuse their paychecks in a show of solidarity with federal employees affected by the shutdown.

So far, 64 members of Congress say they will turn down their paychecks during the partial government shutdown, according to social media posts and statements reviewed by CNN.

That comprises 13 senators and 51 representatives, with members from both parties making up a similar proportion of those going without pay. Fourteen representatives passing on pay are newly elected and were sworn in this year.

Read the full list of lawmakers here.

With about 41% of the US Food and Drug Administration off the job due to the government shutdown, some agency employees worry about the safety and health of the American public.

"With the shutdown, surveillance is not effective. They are doing the bare minimum to get by," said Geneve Parks, a chemist who tests pharmaceuticals at an FDA lab in Detroit. She says she loves her work but is furloughed along with about half of the 34 to 40 people who work in her lab. Now, she estimates that there are only five people in the chemistry division.

"It's terrifying. What if there's an outbreak?" Parks asked. "What would the agency do if something happened and they don't have the staff to handle it?"

Keep reading.

Republican Congressman Will Hurd — oftentimes a thorn in his party’s side as he breaks on issues — told CNN that he more or less did not find the Vice President Mike Pence’s argument persuasive in a caucus meeting today.

Asked how he would vote on the individual spending bills that Pelosi plans to bring to the floor this week, Hurd demurred.

“We’re still evaluating. My opinion is very simple: we should not negotiate with shutdowns, shutdowns don’t help anybody," he said.

Sen. Lisa Murkowski, a Republican from Alaska, joined calls today to reopen the rest of the federal government before the funding fight over the border wall is resolved.

“I am one who is amendable to a process that would allow for those appropriations bills that have concluded some time ago that they be enacted into law — whether it’s the Department of Interior or the IRS. I’d like to see that," she said.

Murkowski said she supports a legislative package made up of six full-year spending bills to reopen other shuttered parts of the federal government.

“I am supportive of a process that is going to allow us to get these six bills through and if we need need to do something with homeland ... let’s do that. But I think we can walk and chew gum," she said.

Senate Democrats blocked action on a bill unrelated to the ongoing government shutdown Tuesday, in protest of President Donald Trump’s demands to fund a controversial border wall with Mexico in exchange for reopening the agencies. 

The move escalated an already tense situation between the parties as Democrats weighed whether to extend their objections to all legislation until the impasse is broken, something that could cripple the chamber and add to the dysfunction in the nation’s capital. 

The vote — the first roll call of the new session — came on a package of bipartisan bills related to US support for Israel and Jordan and new sanctions against the Syrian regime. Needing 60 votes to break a filibuster, the motion was defeated 56-44.

Three Democrats from red states voted with Republicans: 

They were joined by a fourth Democrat, foreign relations ranking member Bob Menendez, in voting yes.

Republican Sen. Richard Shelby, the chairman of the Senate Appropriations Committee, said he is going to support the Mitch McConnell’s position when it comes to not bringing up any of the appropriations bills from the House this week.

It’s getting harder and harder for some Republicans to take the heat on the government shutdown and the House is expected to pass individual appropriations bills this week that the Senate already supported. But Shelby said he supports McConnell’s decision not to bring them up.

He said it would be “futile” to put bills on the floor that won’t get President Trump’s signature.

“I guess it's optics versus substance," Shelby said.

Asked if he would support Trump declaring a national emergency for funding for the wall, Shelby said, "I don’t know we will have to wait and see what he has to say about it."

“Let’s be honest. The shutdown is not nice," the Alabama lawmaker said. “It’s a partial shutdown, but it’s about a total of 800,000 workers and a lot of ‘em are going to be without paychecks soon and we need to do everything we can to do our job and do it on time.”