President Trump Donald John TrumpFederal prosecutor speaks out, says Barr 'has brought shame' on Justice Dept. Former Pence aide: White House staffers discussed Trump refusing to leave office Progressive group buys domain name of Trump's No. 1 Supreme Court pick MORE’s approval ticked up to 49 percent — its highest mark this year, according to a new Hill-HarrisX survey released on Wednesday.

The figure marks a 2-point increase from a Sept. 11-12 poll, but a 2-point decrease from its previous peak of 51 percent in August 2018.

Trump's disapproval rating, meanwhile, dropped to 51 percent, which marks his lowest level so far this year.

The nationwide survey was conducted on Sept. 28 and 29, less than a week after House Democrats launched a formal impeachment inquiry into Trump over concerns raised in a whistleblower's complaint about the president's communications with Ukraine.

House Democrats threatened Wednesday morning to subpoena the White House for documents related to Trump’s dealings with Ukraine as part of their impeachment inquiry.

House Oversight Committee Chairman Elijah Cummings Elijah Eugene CummingsBlack GOP candidate accuses Behar of wearing black face in heated interview Overnight Health Care: US won't join global coronavirus vaccine initiative | Federal panel lays out initial priorities for COVID-19 vaccine distribution | NIH panel: 'Insufficient data' to show treatment touted by Trump works House Oversight Democrats to subpoena AbbVie in drug pricing probe MORE (D-Md.) said in a memo that House committees have repeatedly tried to obtain voluntary compliance from Trump officials, but the White House has “refused to engage with — or even respond to — the Committees."

Speaker Nancy Pelosi Nancy PelosiDemocratic senator to party: 'A little message discipline wouldn't kill us' Overnight Health Care: New wave of COVID-19 cases builds in US | Florida to lift all coronavirus restrictions on restaurants, bars | Trump stirs questions with 0 drug coupon plan Overnight Defense: Appeals court revives House lawsuit against military funding for border wall | Dems push for limits on transferring military gear to police | Lawmakers ask for IG probe into Pentagon's use of COVID-19 funds MORE (D-Calif.) and House Intelligence Committee Chairman Adam Schiff Adam Bennett SchiffSchiff to subpoena top DHS official, alleges whistleblower deposition is being stonewalled Schiff claims DHS is blocking whistleblower's access to records before testimony GOP lawmakers distance themselves from Trump comments on transfer of power MORE (D-Calif.) held a joint news conference later that morning, warning that attempts by the White House to “stonewall” the impeachment inquiry and “conceal facts” would be considered an obstruction of justice.

President Trump, meanwhile, has warned about the implications of a potential impeachment, and claimed that Democrats are just trying to hurt the country.

"The Do Nothing Democrats should be focused on building up our Country, not wasting everyone’s time and energy on BULLSHIT," Trump tweeted following the news conference.

HarrisX researchers surveyed 1,000 registered voters. The margin of error for the full sample is plus or minus 3.1 percentage points.

—Tess Bonn