The first strike by Hollywood writers in nearly 20 years got under way yesterday with noisy pickets on both coasts after last-minute negotiations Sunday failed to produce a deal on payments to writers from shows offered on the Internet.

The first noisy strikers appeared outside the “Today” show set at Rockefeller Center, where NBC is headquartered. The show is not directly affected by the strike because news writers are part of a different union.

A giant, inflated rat was displayed, as about 40 people shouted, “No contract, no shows!”

No new negotiations were scheduled, although the writers guild negotiating committee did plan a meeting of its members.

The chief negotiator for the Alliance of Motion Picture and Television Producers, Nick Counter, said he expected a long standoff.

“We’re hunkered down for a long one,” he said. “From our standpoint, we made every good faith effort to negotiate a deal, and they went on strike. At some point, conversations will take place. But not now.”

Writers said the next move was up to the studios.

“My hope is that it won’t be too long,” the chief negotiator for the writers, John Bowman, said. “We have more reason to get together than not.”

Mr. Bowman said behind-the-scenes communication was occurring between the two sides with the hope of arranging more meetings.

“They claim that the new media is still too new to structure a model for compensation,” a writer for “Late Night with Conan O’Brien,” Jose Arroyo, said.

“We say give us a percentage so if they make money, we make money,” Mr. Arroyo said.