The United Nations' top court has warned that Russia must protect ethnic rights in Crimea, on the day that Ukraine's president Petro Poroshenko pleaded for the west to maintain the sanctions on Moscow that were imposed after the seizure of the peninsula.
Kiev had appealed to the International Court of Justice (ICJ) in the Hague to demand Russia stop supplying money and arms to Russian-backed separatists in the war-torn Donbass region.
Although the ICJ said there was not enough evidence that Moscow funds were used "to cause death or serious bodily harm to a civilian", it did rule that Moscow must stop "racial discrimination" against minority groups in the Russian-occupied Crimea peninsula.
Earlier on Wednesday (19 April), Poroshenko told the Chatham House think tank that sanctions were the only lever to bring Russia to the table and solve the conflict in the east of the Ukraine that has entered its fourth year and killed nearly 10,000 people.
He said Russia's sending of troops, tanks and artillery into Crimea has turned it into "the world's biggest military base".
Poroshenko said: "Sanctions should stay firm on Russia. Don't believe that sanctions bring nothing, this simply is not true. This is the only mechanism to keep Russia at the table of negotiations. If it wasn't for the sanctions, and the newly-born Ukrainian army, Russian tanks would be standing much deeper in Europe.
"Putin started his campaign with a sense of impunity. Because of the sanctions and the readiness of Ukraine to fight back, he has a sense of hesitation and even that is very important," he told the London think tank.
The Ukrainian president met with British politicians including prime minister Theresa May and the chairman of the All-Party Parliamentary Group on Ukraine in the British parliament, Sir Gerald Howarth, and the chairman of the foreign affairs committee, Crispin Blunt.
Poroshenko has to strike a balance between getting the west's support against Russia and maintaining pressure on the west to keep to the terms of the 1994 Budapest memorandum, in which Ukraine gave up the world's third biggest nuclear arsenal in exchange for security guarantees of its territorial integrity and sovereignty.
Despite not being a member of NATO, Ukraine does get military support and training from alliance members, including the UK.
Poroshenko referred to that co-operation and highlighted how since 2014, 5% of Ukraine's GDP and 30% of its budget is spent on defence and security, which is higher than most NATO member states. He appeared to be implying that it is more committed than some alliance members which do not pay their fair share.
He said that since he was elected as president, the country now has the continent's eighth biggest army which "is the only army that faced Russian aggression and is also capable to contain it effectively". However, a considerable part of the Ukraine's military defence in the Donbass region does rely on the efforts of civilian forces.
Russian 'problem of attitude'
Poroshenko told the Chatham House think tank that Russia has a "problem of attitude" which differs from Ukraine's and even that of the Soviet Union.
"The Soviets thought along the lines: 'We are good, they are bad'. The Kremlin thinks along the lines: 'They are bad, so we are allowed to be bad,'" he said.
Poroshenko said that through hybrid war tactics that combined military might, misinformation, propaganda and hacking, Russia "is not only rejecting the world order - it is trying to create an alternative reality based on alternative values".
Wednesday's UN court ruling puts the onus on both Moscow and Kiev to try to implement the Minsk agreements to bring peace.
Ukraine is also demanding compensation for what it says are terrorist acts, such as the attacks on civilian areas and the downing of Malaysian Airlines flight MH17, which Moscow deny. The Kremlin denies it has military involvement in Ukraine.