"As stated in the letter, Parubiy thanked Pence "for the permanent support of Ukraine" and informed on the events of 25 November 2018, when the Russian Federation, violating the sovereignty of Ukraine and worldwide law, attacked the Ukrainian boat "Berdyansk" and "Nikopol", as well as inshore tug "Yana Kapu", captured them, wounding and capturing Ukrainian sailors".
Ukraine said Russian Federation had partially restored access to its ports on the Azov Sea following months of disruption and a week after its navy was sacked on by its neighbor.
Savchenko became a national hero in Ukraine after she was captured by Russia-backed rebels during fighting in eastern Ukraine in 2014 and ended up in a Russian prison.
"Ukraine is constantly considering the Budapest Memorandum as an important global instrument for ensuring Ukraine's security", the ministry said in a statement on its website.
The global community views the annexation as illegal and the election Russian Federation uses to justify it as illegitimate.
Late last month Russian Federation opened fire on and seized three Ukranian navy vessels as they tried to pass through the Kerch Strait.
In a tit-for-tat, Ukrainian President Petro Poroshenko has forbidden Russian male citizens aged 16 to 60 from entering the country.
The Russian Ministry of Foreign Affairs also claimed Wednesday that the Ukrainian government had undertaken "active preparations" for a military offensive in eastern Ukraine, using the recent declaration of martial law in select regions as a cover.
"All of Ukraine is now proud of your loved ones", he said during the emotional meeting in his office, hugging the captives' family members, some teary-eyed.
Russia's Investigative Committee has accused the Ukrainians of illegal border crossing.
A celebrated former Ukrainian military pilot in jail on charges of plotting an attack on parliament said Wednesday that she has started refusing food and water in protest.
"According to their status, according to the Geneva Convention, they are prisoners of war and can not be tried in any Kremlin court", he said.