The U.S. House judiciary committee is moving to authorize subpoenas for several people tied to special counsel Robert Mueller's report, including President Donald Trump's son-in-law, Jared Kushner, and his former attorney general, Jeff Sessions.

The resolution coming up for a vote Thursday would authorize subpoenas for documents and testimony from 12 people in all, including former national security adviser Michael Flynn, the White House's former chief of staff John Kelly and former deputy attorney general Rod Rosenstein.

Lawmakers will also be voting on subpoenas for documents and testimony on the Trump administration's handling of immigration, including the abandoned "zero tolerance" approach of separating migrant families at the southern border.

The resolution authorizes an investigation into whether there have been any discussions of Trump offering pardons to Homeland Security officials who work on immigration issues.

Judiciary chair Jerrold Nadler, a Democrat from New York, will make the final decision about issuing the subpoenas. He said they can be avoided if the information is provided voluntarily.

The judiciary panel is investigating whether Trump obstructed justice after Mueller's report detailed several episodes in which Trump tried to influence his investigation. Mueller said he could not exonerate Trump on obstruction and indicated in a May news conference it was up to Congress to decide what to do with his findings. Mueller is scheduled to testify to Congress next week.

Former attorney general Jeff Sessions, pictured with Trump in December, 2017. (Evan Vucci/Associated Press)

Democrats have had little luck in their attempts to investigate beyond what Mueller detailed in his 448-page report, as the White House has blocked several witnesses from answering questions. It's unclear if they would have better luck with the latest group of witnesses, as most worked for the White House or the administration.

Still, Democrats say they will call in the witnesses as they attempt to keep public attention on Mueller's report. And Nadler has said the panel is preparing a lawsuit to challenge the efforts to block testimony.

Looking into 'catch-and-kill'

Among the other subpoena targets are Corey Lewandowski, Trump's former campaign manager; Jody Hunt, Sessions's former chief of staff, and former White House aides Rob Porter and Rick Dearborn.

Three other names on the list are related to the National Enquirer's efforts to help kill potentially embarrassing stories about Trump over the years by paying hush money in a practice known as "catch-and-kill." Former Trump lawyer Michael Cohen discussed the practice in testimony before the House oversight and reform committee earlier this year.

They include:

David Pecker, chief executive of the National Enquirer's parent company and a longtime Trump ally.

Dylan Howard, who Cohen said was personally involved in co-ordinating payments to two women who said they had affairs with Trump.

Keith Davidson, a lawyer who initially represented the women and negotiated their payments.

Republicans have fought the Democratic efforts to investigate obstruction, saying the issue should be laid to rest after the Mueller report.

"Today's latest effort to relitigate the special counsel's investigation remains unimpressive and unproductive," said the top Republican on the judiciary panel, Georgia Rep. Doug Collins. "Mr. Mueller's team issued more than 2,800 subpoenas before concluding that no Americans conspired with Russia.

"Even if chairman Nadler still believes subpoenas are conversation starters, it's hard to imagine this handful of subpoenas will do anything but reinforce the principal conclusions we've been able to read about for months."

Separately on Tuesday, Felix Sater, a Russia-born business executive who worked with Trump's associates on an effort to build a skyscraper in Moscow, sat down for an interview with staff on the House intelligence committee. The panel's chairman, Democratic California Rep. Adam Schiff, subpoenaed Sater last month after he didn't show up for a scheduled interview.

Sater worked with Trump's former personal lawyer, Michael Cohen, on the skyscraper deal before the 2016 election. The project was later abandoned, and Cohen is now in prison, partly on charges that he lied to Congress about the project.