Ukrainian leader says Putin wants his whole country, asks for NATO help

'FORTRESS CRIMEA'

There were further signs that Russia was pressing ahead with its plans to fortify Crimea and turn it into what Kremlin-backed media have called a fortress.

Russia on Thursday deployed a new battalion of advanced S-400 surface-to-air missile systems in Crimea, its fourth such, TASS news agency cited a spokesman for Russia's Black Sea Fleet as saying.

Citing a Crimean security source, Interfax news agency also reported Russian plans to build a new missile early-warning radar station in Crimea next year that would be able to track ballistic and cruise missiles from a long distance.

Russia was also working on a new technical system to allow it to better track shipping around the peninsula in order to protect its maritime borders, Interfax said.

The United States and the EU have both imposed sanctions on Russia over its conduct towards Ukraine since 2014, when Moscow seized and annexed Crimea after a pro-Russian leader was toppled in Kiev.

Moscow later backed pro-Russian separatists in eastern Ukraine in a conflict in which more than 10,000 people have been killed. Major fighting ended with a 2015 ceasefire but deadly exchanges of fire are still frequent.

Poroshenko, whom Putin has accused of manufacturing the Black Sea crisis to boost his flagging ratings before an election next year, called on Germany to halt an undersea pipeline project that would allow Russia to supply more gas to Germany directly.

The Nord Stream 2 project is a potentially serious problem for Ukraine which currently earns large transit fees from piping Russian gas to Europe and stands to lose out.

"We need a strong, resolute and clear reaction to Russia's aggressive behaviour," Poroshenko told Funke. "That also means stopping the Nord Stream 2 gas pipeline project."

But Germany's economy minister dismissed the idea that his country's commitment to the pipeline undermined efforts to de-escalate the Ukraine crisis.

"These are two separate questions," Peter Altmaier told the ARD public broadcaster.

Poroshenko's attempts to get the EU to impose new sanctions on Russia appeared to be falling flat.

Heeding his suggestion, the EU's hawks have called for more sanctions but the divided bloc is not going to act swiftly, if at all, diplomatic sources have said.

German Chancellor Angela Merkel said she would raise the Black Sea issue with Putin at a G20 summit which starts in Argentina on Friday where the Russian leader is also due to hold talks with U.S. President Donald Trump.

NATO has urged Russia to release the three Ukrainian navy ships and their crews, saying there was no justification for Moscow's actions. But the military alliance, which Ukraine one day hopes to join, has stopped short of offering to deploy new forces in the area to deter Russia.