"This is a president who wants to see something done, but he wants to see it done right", Sanders said. Sanders went on to say that Jackson "exhausted just about every question that you guys have" while calling him the "only credible source" to comment on the president's health.
She could also face questions about a potential government shutdown.
Republicans have accused Democrats of holding up budget talks in order to secure long-term protections for those in the US under DACA.
Negotiations on an immigration deal between the White House and Congress appear to have stalled in recent days following reports that Trump used the expletive characterization during a meeting late last week.
Sanders responded by pointing out that Republicans didn't have the 60 votes they needed to block a filibuster in the Senate.More news: Meghan Markle's half-sister has words for future brother-in-law Prince Harry
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Sanders said Democrats attacking the president over his alleged expletive descriptor are playing politics and "using it as an excuse not to help this president get something accomplished".
"So Democrats either need to decide that they are going to come here to do their jobs and they are going to govern or they're going to put their national security ahead of their own personal, political agendas, or they're not".
Republican leaders proposed a short-term measure Tuesday evening to extend funding through February 16, an acknowledgment of an ongoing disagreement over the future of the Deferred Action for Childhood Arrivals (DACA) program that has stopped Democrats from supporting a longer plan.
That seems unlikely, however, as Democrats disagreed with Trump's repeated demand that Congress offer border wall funding in exchange for a DACA fix. After yet another eventual day, Sanders returned to meet with the media, as reported by ABC News on January 17.