German Foreign Minister Heiko Maas on Tuesday urged Moscow to stick to international law again and respect the territorial sovereignty of neighbouring countries, following Russia's seizure of Ukrainian vessels.
Ukraine's President Petro Poroshenko has warned of an "extremely serious" threat of a land invasion after Russia seized three Ukrainian naval ships and took their crew prisoner at the weekend.
"The aim must be that Russia sticks to international rules again and that it does not violate the territorial sovereignty of its neighbours," Maas said in a speech in Berlin.
To achieve this, Germany and its European allies need clear principles and a "true dialogue" on common security in Europe, Maas added.
Russia has stopped three Ukrainian navy vessels from entering the Sea of Azov via the Kerch Strait by placing a huge cargo ship beneath a Russian-controlled bridge, Russia's state-controlled Rossiya 24 TV channel reported on Sunday.Earlier on Sunday, Russia and Ukraine accused each other of breaking international law after Russian border guards tried and failed to stop Ukrainian ships circumnavigating Crimea en route to a Ukrainian port.A Rossiya 24 correspondent reporting from the area of the Kerch Strait bridge near Crimea said Russia's tactic had completely blocked the bridge, which connects the Black Sea and the Sea of Azov, and that Russian military helicopters were circling overhead.
Russia blocks Ukrainian navy from entering Sea of Azov

German Defence Minister Ursula von der Leyen
"Russia to free Ukrainian sailors immediately"
Meanwhile, German Defence Minister Ursula von der Leyen urged Russia on Tuesday to release Ukrainian sailors captured at the weekend and said both parties needed to show they were trying to calm the situation.
Russia seized three Ukrainian naval ships and took their crew prisoner at the weekend, prompting Ukraine's President Petro Poroshenko to say there was now an "extremely serious" threat of a Russian land invasion.
Von der Leyen told the Berlin Security Conference that the circumstances were not yet fully understood, but it was critical to avoid the situation spiralling out of control.
"This is about the question of respect for territorial integrity and about the will not to let disputes escalate," she said.
"The Kremlin has violated these rules and principles in the past years. In this current situation, both sides, Russia and Ukraine, must show that they are actively contributing to de-escalation," von der Leyen added.
She said the seized ships and sailors must be released. "Ukraine must provide evidence about the exact events. Russia must ensure free passage through waterways and it should not act in an disproportionate way," she added.
German Chancellor Angela Merkel spoke to Russian President Vladimir Putin on Monday and stressed the need for de-escalation and dialogue, her spokesman said on Tuesday.
Russia on Sunday intervened as Ukrainian warships were engaged in relocation from the Port of Odesa to the Port of Mariupol in the Sea of Azov, the Ukrainian navy said.According to a statement by the Ukrainian Navy, two armored artillery vessels and a tug boat were sent after notifying transfer plans in advance, in accordance with international rules, to ensure the safety of shipping.The statement said Russian ships tried to stop the movement by “ramming” the tugboat that caused minor damages.It said all “unlawful” actions were recorded by the Ukrainian Navy Command and transferred to the international bodies.However, the Russian Federal Security Service (FSB) claimed that Ukraine violated international law by crossing the Sea of Azov, off the Crimea.Relatives of MH17 victims taking Russia to top EU courtIn a statement, the FSB said the Ukrainian warships illegally entered Russian territorial waters at 07.00 a.m. local time.The statement added that the Ukrainian ships were carrying out “dangerous maneuvers” in the Russian waters, ignoring the warnings of the border security.Ukrainian ships continued its “provocation for around five hours in the territorial waters of Russia,” the statement said, added: "The purpose of the Ukrainian ships in the region to create a conflict is obvious."Bulgaria reported as route choice for TurkStream 2 gasHead of Russian spy agency accused of British poison attack dies
Russia ‘rams’ Ukrainian tugboat off Crimea
Relatives of the victims of the Malaysian Airlines flight shot down in 2014 are taking Russia to the European Court of Human Rights, Dutch media reported on Friday. A law firm based in Amsterdam issued a formal complaint against Russia to the court on behalf of relatives of 55 people who died in the MH17 disaster, DutchNews.nl reported. The website quoted lawyer Veeru Mewa saying: “My clients have the impression that Russia has not delivered important information to the Joint Investigation Team.” “In addition, Russia has come forward with facts which have later transpired not to be true,” he added. According to DutchNews.nl, if the case is accepted, it would take around five to seven years to be processed. This May a team of international investigators implicated Russia in the crash of flight MH17, which was shot down while flying over eastern Ukraine, killing all 283 passengers and 15 crew on board.
Relatives of MH17 victims taking Russia to top EU court