Nearly 16,000 foreign volunteers from 72 countries are serving in Ukraine's armed forces, a military official said on Thursday.
Almost 40% of the foreign fighters come from Latin American countries, military ombudsman Olha Reshetylova was quoted as saying by the Interfax-Ukraine news agency.
President Volodymyr Zelensky has said Ukraine's armed forces number around 880,000 soldiers.
In June, then-defence minister Mykhailo Fedorov announced plans to increase the share of foreign recruits in assault and infantry units to as much as 50%.
Kiev is seeking to attract recruits from around the world by offering an average monthly salary equivalent to about $6,700.
Ukraine established its International Legion shortly after Russia launched its full-scale invasion in 2022 to recruit foreign volunteers. Foreign fighters are also serving on the Russian side.