(CNN) - President Barack Obama joined Vice President Joe Biden at a dinner with Republican senators Sunday night to talk about Syria. The dinner took place at the Naval Observatory in Washington.
The GOP dinner comes two days before Obama is slated to go to Capitol Hill and make his case to Senate Democrats as he tries to generate congressional support for military strikes in Syria, a Senate leadership aide confirmed Sunday.
Congress officially returns to Washington Monday after a monthlong summer recess to debate and vote on a resolution giving Obama the authorization to take military action in Syria.
How the Syria debate in Congress could play out this week
While the Senate Foreign Relations Committee passed a resolution last week to authorize the president's proposal, Obama's pitch still faces an uncertain future in Congress.
His trip to Congress will come on the same day he is scheduled to address the nation from the White House in a televised address at 9 p.m. ET. Obama last traveled to the other end of Pennsylvania Avenue at the end of July to speak with House and Senate Democrats before the recess.
Capitol Hill gets off to a busy start on Monday, with all House members getting an intelligence briefing from Secretary of State John Kerry, Secretary of Defense Chuck Hagel, National Security Adviser Susan Rice, Joint Chiefs Chairman Martin Dempsey and Director of National Intelligence James Clapper.
Rice will also brief members of the Congressional Black Caucus.
Obama will give a preview of his address to the nation when he does a round of interviews on Monday with major TV and cable outlets. CNN's Wolf Blitzer will report on his interview with the president on The Situation Room at 6 p.m. ET.
Lawmakers predict rocky future for Syria proposal
The House Homeland Security Committee also scheduled a hearing on Syria for Tuesday morning.
- CNN's Ted Barrett, Deirdre Walsh and Ashley Killough contributed to this report.