The United States is "reviewing" a request from Ukraine's leaders for arms and other military assistance, officials said Thursday, denying reports they had rejected Kiev's appeal.

The requests cover a range of both lethal and non-lethal aid, including intelligence support, ammunition and weapons, administration officials said.

"We are reviewing and working through a series of requests that they have made," a defense official, who spoke on condition of anonymity, told AFP.

But no final decision had been made, two officials said.

The US administration had agreed to one of the requests, pledging to provide the Ukrainians with supplies of military rations known as MREs, or "meals ready to eat," the officials said.

The appeal to the Pentagon coincided with a visit to the United States by the country's new premier, Arseniy Yatsenyuk, who addressed an emergency session of the UN Security Council on Thursday.

President Barack Obama's administration has denounced Russia's intervention in Ukraine but has virtually ruled out military action while trying to promote a diplomatic solution to the crisis.

The Wall Street Journal reported that US officials have rebuffed Kiev's request, at least for the moment, as the Obama administration is worried about stoking tensions with Moscow or triggering an all-out war between Ukraine and Russia.

The Journal, citing unnamed officials, said Ukraine had made a detailed request for aid that included communications gear, aviation fuel, night vision goggles and other items.

The Pentagon had said previously that Defense Secretary Chuck Hagel spoke Friday to his Ukrainian counterpart who asked for technical advice on humanitarian assistance and disaster relief operations.

Hagel said that he would consider any requests for assistance from Ukraine, according to Pentagon officials.

Since the crisis erupted, the US military has steered clear of direct support to Ukraine.

But it has suspended defense cooperation with Russia and sought to reassure anxious allies in Eastern Europe, deploying F-15 aircraft for air patrols over Baltic states and F-16 fighters to Poland for stepped-up aviation training.

US Navy destroyer to conduct more Black Sea drills: commander
Sofia (AFP) March 15, 2014 - A US Navy guided-missile destroyer will remain in the Black Sea to conduct more exercises with allied ships, its commander said on Saturday, the eve of a breakaway vote in Crimea.

The USS Truxtun this week conducted joint exercises with Romanian and Bulgarian naval forces just a few hundred kilometres (miles) away from the disputed Crimea peninsula.

"I cannot comment on our future operations but we will take the opportunity to do some routine exercises with our allies in the region," said Commander Andrew Biehn.

Speaking to reporters aboard the 300-crew ship at the Black Sea port of Varna, Biehn refused to provide details about the drills or the next port of dock of the destroyer, which will leave Varna on Sunday.

The drills were routine and had been "planned a long time before the start of the Crimean crisis." They did not include live firing, he said.

The move comes just days after the Pentagon sought to reassure anxious allies in Central and Eastern Europe over Russia's actions in Ukraine, announcing plans to send more F-15 fighter jets to patrol the skies over Baltic states and stepping up aviation training in Poland.

Pro-Russian forces have taken de facto control of the Crimean peninsula, where a controversial referendum on breaking away from Ukraine to join Russia will be held on Sunday.

The only other US naval ship deployed in the Black Sea is the USS Taylor, a frigate undergoing repairs at the Turkish port of Samsun after having run aground last month.