Congress returned to work on Monday amid the first full week of forced spending cuts, with President Barack Obama and Republicans sticking to deeply entrenched positions that have caused a series of showdowns manufactured by Washington politics.

Most predicted impacts of the $85 billion in cuts that took effect on Friday night -- such as unpaid furloughs for government workers -- won't be evident until April at the earliest, officials say.

But some impacts were already being felt.

Homeland Security Secretary Janet Napolitano told reporters that customs lines for passengers arriving from overseas at some international airports over the weekend were longer than usual due to the spending cuts.

At New York's John F. Kennedy International Airport, more than 50 flights had wait times exceeding two hours and 14 were over three hours, according to Jenny Burke, a spokeswoman for Customs and Border Protection.

"These wait times are not typical for this time period, and are related to decreased booth staffing," Burke told CNN.

In Cody, Wyoming, the local chamber of commerce said Yellowstone National Park will delay the opening of its North and West entrances by a week until April 26, and its East, South and Northeast entrances by two weeks until mid-to-late May due to the impact budget cuts will have on snow removal. The delay will cost related businesses several million dollars, according to the group's estimates.

At an education conference in Washington, school superintendents outlined the impact of the federal government's latest fiscal saga on on their operations, which included job cuts in some cases.

Susan Smit, a superintendent in Wagner, South Dakota, said her district prepared last year in anticipation of reduced federal funding.

"We had to make the cuts," Smit said, noting that changes included reduced health benefits and staff members who were not rehired.

Meanwhile, the partisan rhetoric by both sides seeking to cast blame on the other continued unabated, signaling continued political brinksmanship over tax and spending issues beginning with the March 27 deadline for Congress to authorize funding to run the government until the current fiscal year ends on September 30.

In a first salvo by House Republicans on Monday, their proposal for the government funding measure -- known as a continuing resolution -- sought to soften the impact of the spending cuts on defense and security spending.

Under the proposal unveiled by House Appropriations Committee Chairman Hal Rogers, R-Kentucky, the total government spending for the fiscal year would adhere to the figure negotiated by Obama and Congress minus the cuts.

However, the proposal would allow Pentagon officials to shift funding to protect top priority programs, and also include provisions to maintain FBI and border security spending.

In addition, it would prohibit any spending for transferring terrorism suspects from the Guantanamo Bay, Cuba, detention facility or for renovating a mainland prison to accept such detainees -- a political issue rather than a core spending matter.

House Speaker John Boehner, the top Republican negotiator on fiscal issues, told NBC's "Meet the Press" in an interview broadcast Sunday that he was "hopeful" for a funding agreement to prevent a partial government shutdown on March 27.

Senate Republican leader Mitch McConnell offered a similar prediction on CNN, saying, "I believe we're going to be able to work out passing the continuing resolution later in March on a bipartisan basis through both the House and the Senate."

In reaction to Boehner's comments, the White House issued a statement that stressed its support for a continuing resolution that is "clean" from unrelated items.

It said Congress should act separately to replace the forced spending cuts with alternatives that will be less harmful to the economy.

Obama made clear Friday that the current law requires cuts this fiscal year, which are the first installment of about $1 trillion in spending reductions over the next decade, to be reflected in the continuing resolution to fund the government.

At his first Cabinet meeting of his second term on Monday, the president warned of impending hardship from the forced spending cuts.

"We're going to do our best to make sure that our agencies have the support they need to try to make some very difficult decisions, understanding that there are going to be families and communities that are hurting and that this will slow our growth," Obama said. "It will mean lower employment in the United States than otherwise would have been, but we can manage through it."

In the NBC interview, Boehner said he was uncertain if the forced cuts -- known in Washington jargon as sequestration -- would hurt the economy, as predicted by Obama, economists and most Democrats and Republicans.

Boehner argued in a recent op-ed that the cuts would threaten "U.S. national security, thousands of jobs and more," but he told NBC that "I don't think anyone quite understands how the sequester is really going to work."

Obama had argued at a news conference on Friday -- a few hours before he signed an order implementing the mandatory cuts -- that any resulting harm to the economy would be the fault of GOP intransigence.