"We have sent a protest note to the German Foreign Ministry due to illegal visit of German politicians to Crimea," Melnyk tweeted.
He also said that the deputies could face a ban on entry to Ukraine.
"The illegal entry into Crimea is not a trivial matter, it is a serious crime," the ambassador said.
Направили ноту протесту до МЗС ФРН із-за нелегального візиту до Криму GER політиків: #embinterview@DerSPIEGELpic.twitter.com/vSj0vqUdLU
— Andrij Melnyk (@MelnykAndrij) 23 квітня 2016 р.
As reported earlier, the trip of Frohnmaier and Pretzell to Crimea was aimed to participate in Yalta International Economic Forum organized by the occupation authorities of Crimea. According to media reports, the forum was also attended by MEP Jaromir Kolichek (Czech Republic), MPs Axel Kassegger and Barbara Rosenkranz (Austria), and MP Stefano Valdegamberi (Italy).