Moldova said a Russian missile had violated its airspace on Friday morning and summoned the Russian ambassador to make a formal protest.
The country's foreign ministry said Moscow's ambassador would be summoned "to indicate to the Russian side the unacceptable violation of our airspace by a Russian missile that today flew over the sovereign territory of the Republic of Moldova."
The foreign ministry of the country, wedged between Ukraine and Romania, added that "the Russian side continues its war of aggression against Ukraine and the missile attacks against our neighboring country affects directly and negatively our country."
Ukraine's top general, Valeriy Zaluzhnyi, had earlier said two Russian Kaliber missiles had crossed into Romanian and Moldovan airspace before entering Ukraine, he said.
Valeriy Zaluzhnyi, commander-in-chief of Ukraine's armed forces, said the missiles had been launched from the Black Sea and had entered Moldovan airspace. They then flew into Romanian airspace, before entering Ukraine.
Ukrainian President Volodymyr Zelenskyy reiterated that Russian missiles had flown over Moldova and NATO member Romania on Friday, saying they were a challenge to the collective security of the military alliance.
"The enemy launched at least 70 rockets in another massive attack [on Ukraine] this morning," Zelenskiy said. "Several Russian missiles passed through the airspace of Moldova and Romania. These missiles are a challenge to NATO and collective security. This is terror that can and must be stopped."
However, the Romanian defense ministry said the missile flew some 35 kilometers (about 22 miles) northeast of its border.
"The Romanian Air Force's surveillance system detected on Friday an air target, most likely a cruise missile launched from a Russian ship in the Black Sea near the Crimean Peninsula," the ministry said in a statement.
"The closest the target trajectory got to Romania's airspace was recorded by the radar at roughly 35 kilometers northeast of the border."
A pro-Russian breakaway regime has ruled part of Moldova's territory, Transnistria, since the early 1990s after a separatist conflict. Moldova's intelligence service on Thursday warned that Russia was acting to destabilize the country, which was formerly part of the Soviet Union, reports DW.