Walker, who has said as many as 1,500 workers might lose their jobs, did not specify the number of jobs at risk in his notification to the unions, the Milwaukee Journal Sentinel reported. In a news release, the governor said layoffs might be averted if state lawmakers agree on a budget-repair bill within 15 days.
Also Friday, the AFL-CIO announced it would stage more pro-union rallies in the state Capitol and elsewhere Saturday and Sunday.
"Come stand up for worker rights and Wisconsin's middle class this weekend as we rally in Madison and around the state," the union said in a message posted on its Web site.
Republicans in the Wisconsin Legislature canceled a voting session scheduled for Friday amid reports of negotiations to end the budget impasse. Sources on the Republican side told the Journal Sentinel the items on the table include at least two points in Walker's plan to change collective bargaining for state and local employees.
One would limit unionized public employee wage increases to the rate of inflation and the other would require unions to be re-certified by their members every year.
Walker has said layoffs are needed to save $30 million. Democrats said Walker has other options and does not need to resort to layoffs.
Democratic members of the Wisconsin Senate have been out of the state since Feb. 17 to prevent passage of Walker's "budget-repair bill," which would eliminate most collective bargaining for public-employee unions.
At least 20 senators must be present to pass the bill, but Republicans hold just 19 seats.
Republican senators voted 19-0 Thursday to find their Democratic colleagues in contempt and directed that they be taken into custody. The resolution asserts the Democrats are violating a Senate rule that requires senators to receive a leave of absence before being absent for a day.
"We simply cannot have democracy be held hostage because the minority wants to prove a point," Senate Majority Leader Scott Fitzgerald said.
State Sen. Chris Larson, a Democrat, questioned the motion's legality and told the Wisconsin State Journal the Republicans' "bullying tactics" had produced "an even greater divide in our state."
Republican Attorney General J.B. Van Hollen told the Journal Sentinel he had not advised the GOP senators on the resolution and he had not reviewed it to know if it was constitutional.
The state constitution prohibits the arrest of legislators while in session unless they're suspected of committing felonies, treason or breach of the peace, the State Journal said. But a lawyer for Fitzgerald said rounding up senators was legal under a provision that lets the Senate enforce its own rules.
Thursday's resolution does not call for the senators' extradition from Illinois, where many of them went. It says the senators may be fined $100 a day, starting Friday, for every day they're not in session.
A judge ruled Thursday the state must give protesters fuller access to the state Capitol by 8 a.m. Monday. Dane County Judge John Albert said the state may impose "reasonable restraints" on the time, place and manner of future protests, and he ordered protesters who have spent the night in the Capitol removed by 6 p.m., when the Capitol normally closes.
But Albert said the state had "closed the Capitol impermissibly" since it began restricting public access to the building Monday. He rejected Walker administration arguments the two weeks of protests were so disruptive that public access needed to be slowed to a trickle, the State Journal reported.
The state Department of Administration had shut down all access to the Capitol except to employees, media representatives and members of the public attending hearings or meeting with their senators or representatives.
Albert said his intent was to facilitate the reopening of the Capitol consistent with the free-assembly and free-speech provisions of the state and U.S. constitutions.
By 9:30 p.m. Thursday, the last group of about 50 demonstrators left the Capitol with a group hug and a rousing rendition of "Solidarity Forever," the Journal Sentinel said.