Twitter carried pictures of protesting Asian workers and news reports said the Obama-Abe bargaining in Japan would probably not result in approval of the trade pact.
He was arrested in June 2011 and sentenced to 11 years in prison on charges widely levelled against trade unionists.
Obando is a sociologist and documentary filmmaker. A week before her arrest, she issued a report documenting the murders of 1500 FENSUAGRO union members. FENSUAGRO is Colombia's largest agricultural workers' union.
Transport grinds to a halt and schools close as thousands march through Athens in protest.
Paraguayan labor federations and small farmer organizations launched a general strike on March 26. Some 90 percent of workers in Asuncion honored the strike.