Story highlights Sources familiar with ongoing talks say there were no substantial developments over recess

The meeting Wednesday is designed to discuss a deal on budget caps

Washington (CNN) Leaders of Congress will sit down with key White House staff on Wednesday, and negotiations on immigration policy could hang in the balance.

As the Senate comes back Wednesday and the House is set to follow next week, lawmakers are returning to their unfinished business that was punted at the end of last year -- including a potential deal on the Deferred Action for Childhood Arrivals policy.

Sources familiar with ongoing talks say there were no substantial developments over recess, although senators working on negotiations did keep talking and several groups in the House left town with all-but-completed outlines that they opted to wait on rather than leave open to public attack over the break.

But even as negotiations have been making progress, lawmakers have felt President Donald Trump's personal buy-in has remained elusive and, yet, the key to any ultimate deal.

The meeting Wednesday is designed to discuss a deal on budget caps on domestic and military spending with the White House legislative chief and director of the Office of Management and Budget. But Democrats have insisted that any spending deal correspond with resolving DACA -- an Obama administration program that protected young undocumented immigrants who came to the US as children from deportation, which Trump has elected to end.

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