Two major unions urged their members to hold a one-day strike and join demonstrations in response to a police crackdown against activists who led a wave of protest that have centered on Istanbul's Taksim Square and Gezi Park in recent weeks.
The show of labor force follows a weekend in which police purged activists from an 18-day sit-in at the park that has come to symbolize defiance against the government, while Ergodan's conservative political base held huge rallies in both Istanbul and Ankara.
Monday's rallies had a more structured feel compared with the counterculture-style sit-in at Gezi and spontaneous protests of recent weeks, which at times devolved into clashes between stone-throwing youths and riot police firing tear gas and water cannons.
The rallies went on despite a warning from the interior minister that participants in unlawful demonstrations would "bear the legal consequences."
In Ankara on Monday, thousands of demonstrators waving union flags, jumping and whistling converged at central Kizilay Square in an uneasy face-off about 50 meters away from riot police and a line of trucks.
Turkey's NTV television reported that riot police issued warnings to the demonstrators to disperse, saying the rally was unlawful and authorities would take action if they did not. After about three hours, the protesters left peacefully.
TV images showed hundreds marching in the Aegean Sea coastal city of Izmir.
Behind the strikes were the KESK confederation of public sector workers and DISK, a confederation of labor unions from industries including transport, construction, health care and media. Together they say they represent 330,000 workers. Small unions that group professionals like dentists, doctors and engineers also joined in.
Strikes, however, often have little visible impact on daily life in Turkey, a country of about 75 million, and the call to walk off the job Monday had limited fallout beyond the demonstrations.
Unionists in Istanbul hoped to reach Taksim Square Monday afternoon. But police have maintained a lockdown on the square after unrest continued in pockets of the country overnight.
The standoff between police and protesters began as an environmentalists' rally. But a police crackdown lit a fuse on much broader anger and morphed the movement into a protest against Erdogan's government.
Erdogan's opponents have grown increasingly suspicious about what they consider a gradual erosion of freedoms and secular Turkish values under his Islamic-rooted party's government. It has passed new curbs on alcohol and tried, but later abandoned its plans, to limit women's access to abortion.
Five people, including a policeman, have died and more than 5,000 have been injured, according to a Turkish rights group.
Erdogan has been praised for shepherding Turkey to strong economic growth as many other world economies lagged. But his government's handling of the protests has dented his international reputation. He has blamed the protests on a nebulous plot to destabilize his government and repeatedly lashed out at reports in foreign media and chatter in social media about the situation.
The labor walkout was the second since the protests began. Another took place June 5.
"The first one, we said it's a warning for the government, to listen the streets, to listen the message from the demonstrators, and we asked them to stop this police violence," said Kivanc Eli Acik, a labor leader.
"But after that day, rather than stopping the violence, the excessive police violence and intervention is going much, much bigger. So this is the second warning, the second strong message to the government," he added.
Keaten reported from Ankara, Turkey. Ezgi Akin in Ankara and Burak Sayin in Istanbul contributed.