Lawmakers will gather Tuesday to hear President Obama’s final State of the Union address, just a day before Republicans decamp to Baltimore for their annual policy retreat.

The president’s last State of the Union will come a week after unveiling executive actions on gun control, including measures to expand background checks. His speech is expected to touch heavily on the gun issue, which has frustrated him throughout his presidency.

White House officials have signaled that the president's speech will focus on a broad vision for the country, rather than the policy wish list he has delivered in past State of the Union addresses.

In one notable gesture, Obama plans to leave one of his guest seats in the First Lady’s box empty to pay tribute to victims of gun violence.

“We want them to be seen and understood; that their absence means something to this country,” Obama said on a conference call with Organizing for Action on Friday.

Sen. Chris MurphyChris MurphyDemocrats exploring lawsuit against Trump Senators get North Korea briefing in unusual WH visit Hoyer not insisting on ObamaCare subsidies in spending bill MORE (D-Conn.), meanwhile, said that he would bring Mark Barden, whose 7-year-old son was killed in the Sandy Hook Elementary School shooting, as his guest. 

Murphy said that he hopes the president "will challenge each and every member of Congress to finally stand up to the gun lobby and take action on the issue of gun violence."

Other lawmakers, such as Rep. Keith Ellison (D-Minn.), plan to bring Muslims as their guests as a display of solidarity.

Ellison, the first Muslim American elected to Congress, challenged Speaker Paul RyanPaul RyanOvernight Finance: Lawmakers scramble to avoid shutdown | Why some Republicans worry about Trump's tax plan | Trade tensions with Canada Senate's No. 2 Republican: Border tax 'probably dead' New ObamaCare repeal bill on life support MORE (R-Wis.) to invite a Muslim as one of his guests after he condemned GOP presidential front-runner Donald TrumpDonald TrumpOvernight Energy: Trump set to sign offshore drilling order Bush ethics lawyer: Trump should strip Flynn of military title Dems might begin again with Kamala Harris and California MORE’s proposal to ban Muslims from entering the U.S. But Ryan’s office declined to respond to Ellison, saying it will unveil the Speaker's State of the Union guests on Monday.

South Carolina Gov. Nikki Haley, who is frequently mentioned as a potential vice presidential nominee, will be delivering this year’s official GOP response to Obama.

The day after the State of the Union, House and Senate Republicans will head to Baltimore for their annual policy retreat, lasting through Friday, to discuss a platform going into the 2016 campaign. Both chambers of Congress will consequently only be in session from Monday through midday Wednesday.

Republicans are clamoring for major policy ideas as they campaign for reelection this year and support the party’s presidential nominee. In particular, the GOP is still trying to find a way forward to offer a replacement to ObamaCare after sending a repeal bill of the 2010 law to Obama last week. The president vetoed it. 

North Korea, Iran sanctions

The House will vote this week on legislation to toughen sanctions against North Korea after the country claimed it detonated a hydrogen bomb last week. The measure authored by House Foreign Affairs Committee Chairman Ed Royce (R-Calif.) would block North Korea’s access to hard currency and target its assets for nuclear development.

The measure will be brought up under a fast-track process requiring a two-thirds majority for passage, indicating it will attract broad bipartisan support.

Another bill slated for a House vote this week would prevent the Obama administration from lifting sanctions against Iranian individuals and financial institutions unless it can certify they aren’t affiliated with terror efforts, the Iranian Revolutionary Guard or the country’s ballistic missile program.

“Iran and North Korea’s provocative actions can not go unanswered,” Royce and House Majority Leader Kevin McCarthy (R-Calif.) said in a joint statement.

Audit the Fed

Sen. Rand PaulRand PaulRand Paul to teach a course on dystopias in George Washington University Destructive 'fat cat' tax law a complete flop. It's time to repeal it. Trump must take action in Macedonia to fix damage done by Obama and Clinton MORE (R-Ky.) is getting a long-awaited vote on his controversial proposal to audit the Federal Reserve. 

Senate Majority Leader Mitch McConnellMitch McConnellOvernight Finance: Lawmakers scramble to avoid shutdown | Why some Republicans worry about Trump's tax plan | Trade tensions with Canada Hundreds of former EPA employees blast Trump on climate change Democrats must have a better response on net neutrality than simply 'no' MORE (R-Ky.) set up the Senate to take a procedural vote on the 2016 contender's legislation on Tuesday afternoon, hours ahead of President Obama's final State of the Union. 

But Paul could face an uphill battle to get the 60 votes needed to overcome the procedural hurdle. So far the legislation has 24 cosponsors, all Republicans. 

"The Fed operating under a cloak of secrecy has gone on for far too long," Paul said in a statement last month. "The American people have a right to know exactly how Washington is spending their money.  

The proposal would increase congressional oversight of the Federal Reserve, as well as subject the central bank to an audit by the Government Accountability Office.  

But it's gotten pushback from the Obama administration as well as Sen. Richard Shelby (R-Ala.), who chairs the Senate Banking Committee. 

Environmental regulations

Two measures to combat the Obama administration’s environmental regulatory regime are scheduled for votes in the House this week.

A bill titled the Supporting Transparent Regulatory and Environmental Actions in Mining (STREAM) Act would prevent the Office of Surface Mining (OSM) from finalizing a new mining rule until it goes through an additional scientific review and the administration releases more details about its formation. 

The regulation is designed to update standards for buffer zones around streams where mining and waste are banned. Republicans have passed similar legislation in the past to block the rule’s implementation, most recently in 2014.

The House is also expected to clear a Senate-passed resolution to disapprove of an Obama administration regulation to redefine which waterways are under federal jurisdiction, also known as the Waters of the United States rule. Lawmakers previously considered legislation to overturn the rule last year.

- Devin Henry contributed.