By Adrian Croft and Sabine Siebold
BRUSSELS (Reuters) - The head of NATO said on Wednesday he saw no sign that Russia was respecting its international commitments over Ukraine as Britain warned Moscow it could face tougher European Union sanctions unless it acted to stop fighting in eastern Ukraine.
NATO has already suspended all practical cooperation with Russia over Moscow's annexation of Ukraine's Crimea region though it has kept open high-level political contacts.
"I regret to say that we see no signs that Russia is respecting its international commitments," NATO Secretary-General Anders Fogh Rasmussen told reporters during a meeting of alliance foreign ministers in Brussels.
"So today we will review our relations with Russia and decide what to do next," he said, without specifying how Moscow's actions had fallen short.
British Foreign Secretary William Hague, arriving for the NATO meeting, warned that support for tougher EU sanctions would grow unless Russia acted to defuse violence in eastern Ukraine and to support a peace plan put forward by Ukrainian President Petro Poroshenko.
EU leaders may discuss imposing tough economic sanctions on Russia at a Brussels summit on Friday if they do not see Russian action to support Poroshenko's proposals.
Russian President Vladimir Putin asked Russia's upper house on Tuesday to revoke the right it had granted him to order a military intervention in Ukraine. But at the same time Kiev said pro-Russian rebels in east Ukraine had shot down a military helicopter, most likely killing all nine people on board.
It was the most serious breach of a temporary ceasefire agreed in talks between government and rebels less than 24 hours earlier.
"While there have been welcome words from Russia about that (the peace plan) we have not seen yet the actions to go with that, including tragically the shooting down of a Ukrainian helicopter yesterday with the death of nine more people," Hague told reporters at NATO headquarters.
"So we urge Russia to take the necessary action to stop the flow of arms across the border (and) to stop supporting illegally armed separatist groups in eastern Ukraine because in the absence of that action by Russia the case for stronger sanctions from European Union nations will of course become stronger," Hague said.
German Foreign Minister Frank-Walter Steinmeier called Putin's request to rescind the intervention law good news.
"But seeing the development afterwards – the downing of the helicopter with nine dead – we see how fragile everything is and how quickly progress just reached can be destroyed again by activities of the separatists on the ground in eastern Ukraine, possibly helped by third parties," he said.
"As there is no military option, it is crucial that we - despite the incidents of the last couple of days - leave no possibility unused and try cautious steps for the building of a minimum of trust, trust which has been completely lost between Russia and Ukraine," he said.
(Editing by Andrew Heavens)