Spicer, the Republican National Committee communications director and chief strategist, will "spend more time" with the Trump operation in New York, campaign manager Kellyanne Conway said.
"He's going to be spending more time here," Conway said Sunday on ABC's "This Week."
A source familiar with the move told CNN that how much time Spicer spends working out of the campaign's headquarters each week will vary.
The move comes amid a recent campaign shake-up that saw the departure of campaign chairman Paul Manafort alongside the promotion of Conway to campaign manager and installation of Breitbart executive Steve Bannon as the campaign chief executive.
Trump has had a tense relationship with the RNC throughout the primary and into the campaign season, at times railing on the GOP establishment and accusing the party of working against him.
Since winning the nomination, however, Trump has mostly presented a united front with the RNC, working closely with party brass to thwart an effort by anti-Trump delegates at the Republican convention to block his nomination.
RNC Chairman Reince Priebus has also been a tireless adviser to and supporter of Trump, working to broker peace between Congress and party leaders like House Speaker Paul Ryan and Trump.
The Trump campaign has also said it would rely heavily on RNC organization on the ground across the country, rather than building out new entirely new infrastructure for the campaign.
But the hiring of Bannon -- a longtime RNC critic known for no-holds-barred criticism of the party elite -- had raised eyebrows and concerns over his relationship with the party organization.
Spicer said the RNC and the Trump campaign will work closely together.
"We are committed to winning back the White House and maintaining our majorities in the House and Senate," Spicer said of his role. "To that end, our political, digital, data and communications teams will continue to integrate and coordinate with the the top of the ticket."