President Barack Obama summoned congressional lawmakers to the White House on Wednesday as a partial government shutdown entered a second day with little sign of a breakthrough. Lawmakers from both parties suggested the impasse could last for weeks and grow to encompass a dangerous fight over the U.S. borrowing limit.

The shutdown forced Obama to cancel two stops in his long-planned trip to Asia and left government services in limbo across the country. It even idled many employees of the nation's intelligence services.

The office of the Republican leader of the House, Speaker John Boehner, said he would attend the White House meeting, casting it as a sign the president is ready to start negotiating on Republican demands to extract changes to the new health care law in exchange for funding the government.

Obama has repeatedly said he won't negotiate changes in the law in exchange for reopening the government. An Obama adviser said the president will urge the House Republicans to pass a spending bill free of other demands.

Funding for much of the government was cut off Tuesday after a Republican effort to thwart the health care law stalled the short-term, normally routine spending bill.

Public anger mounted as the partial shutdown closed iconic national parks and monuments and disrupted functions from garbage collection in Washington D.C. to medical research. Nearly a third of the federal workforce — 800,000 employees — were forced off the job. People classified as essential employees — such as air traffic controllers, Border Patrol agents and most food inspectors — continued to work.

Obama to cancel stops in Malaysia and the Philippines, the last two of his Asia tour scheduled to begin Saturday. The White House was re-evaluating the only other two stops in Indonesia and Brunei.

Even intelligence agencies felt the effects. Director of National Intelligence James R. Clapper told Congress that roughly 70 percent of the intelligence workforce — including the CIA and National Security Agency — have been furloughed but he's trying to keep enough people to guard against potential threats.

The increasingly entrenched standoff — and especially concerns of a looming debt limit crisis — rattled stock markets that had largely shrugged off the shutdown on its first day. Stock indexes slipped in the U.S., Germany and France.

Senate Majority Leader Harry Reid, Senate Minority Mitch McConnell, and House Minority Leader Nancy Pelosi, were also to attend the White House meeting.

We're pleased the president finally recognizes that his refusal to negotiate is indefensible," Boehner spokesman Brendan Buck said. "It's unclear why we'd be having this meeting if it's not meant to be a start to serious talks between the two parties."

Reid, the top Senate Democrat, offered a new round of budget talks to House Republicans if they allow the government to reopen. He proposed that the talks occur on a nonbinding measure known as a budget resolution that can serve as a template for follow-up legislation on the budget.

Some Republicans appeared ready to agree to Obama's demand for a straightforward spending bill with no strings attached.

The budget dispute has divided the Republican Party. A core of conservative activists have led a passionate charge against the 2010 health care law, arguing it is hurting jobs and restricting freedom by requiring Americans to have health insurance. But other Republicans fear the party will be blamed for the shutdown and face the consequences in next year's congressional elections.

Rep. Peter King, a New York Republican, charged Wednesday that House members aligned with the small-government tea party movement are trying to "hijack the party."

King said he senses that increasing numbers of House Republicans — perhaps as many as a hundred — are tired of the shutdown. He told MSNBC that Republican lawmakers will be in meetings Wednesday to look for a way out.

Obama was also meeting Wednesday with the chief executives of the nation's 19 largest financial firms, trying to highlight big business opposition to the shutdown. The U.S. Chamber of Commerce had sent a letter to Congress urging no shutdown and warning against a debt ceiling crisis that they say could lead to a disastrous default.

House Republican leader and tea-party backed members seemed determined to press on. The House leadership announced plans to pass five bills to reopen more popular parts of the government, including national parks, processing of veterans' claims and government of Washington, D.C.

The White House immediately promised a veto, saying opening the government on a piecemeal basis is unacceptable.

Across the nation, America roped off its most hallowed symbols, from the Statue of Liberty in New York to the Washington Monument, and shooed campers away from the Grand Canyon and other natural wonders. The far-flung effects reached France, where tourists were barred from the U.S. cemetery overlooking the D-Day beaches at Normandy.

With the shutdown ruining vacations and sapping tourism business, Americans inundated social media to vent their frustration. "You should not be getting paid. In fact, you all should be fired!" Bruce Swedal, a 46-year-old Denver real estate agent, tweeted to Congress members.

Unaffected by the shutdown, a key part of the health plan took effect Tuesday. Health insurance exchanges opened online across the country to take applications for coverage that would start Jan. 1. The new law is intended to extend coverage to the millions of Americans now uninsured.

There were suggestions from leaders in both parties that the shutdown could last for weeks and grow to include a measure need in a couple of weeks or so to increase the debt limit.

"This is now all together," said Sen. Dick Durbin, a Democrat. Rep. Paul Ryan, the Republican House Budget Committee Chairman, added: "I've always believed it was the debt limit that would be the forcing action."

The U.S. risks a market-rattling, first-ever default on its obligations if Congress fails to raise the limit.