(Reuters) -Ecuador's foreign ministry on Tuesday said that it was effectively reinstating a visa requirement for travelers from China, citing an increase in irregular migratory flows from the Asian nation.

The ministry, in a statement posted on social media, said that it was suspending an agreement with China which had waived the requirement for travelers to obtain a visa.

The ministry said that many Chinese travelers had overstayed the permitted 90-day period, with some potentially using Ecuador as a stepping stone to reach other destinations in the region.

The ministry said that in recent months, nearly half of visitors from the country did not exit through regular routes on time.

Asked about Ecuador's visa waiver suspension, Chinese foreign ministry spokesperson Lin Jian said on Tuesday that China firmly opposes all forms of human smuggling.

"The agreement on mutual visa exemption between China and Ecuador, since it took effect in August 2016, has played an important and positive role in promoting cross-border travel and practical cooperation in various fields between the two countries," Lin told a regular news briefing.

China's law enforcement departments are working with relevant countries to jointly tackle human smuggling activities, repatriate illegal immigrants and maintain a good order in cross-border travel, Lin said.

(Reporting by Natalia Siniawski; Additional reporting by Ethan Wang in Beijing; Editing by Kylie Madry and Sharon Singleton)