U.S. senators have once again called on Barack Obama to give weapons to Ukrainian troops fighting pro-Russian rebels in the contested region of eastern Ukraine. The request comes after Democrat whip Dick Durbin met with Ukrainian Prime Minister Arseniy Yatsenyuk on Tuesday and just a day after the White House again ruled out acting on a House resolution in favor of giving Ukraine $300 million of lethal aid.

"Ukraine is at a critical moment in its history," Durbin said. "As Russia continues its unprecedented aggression in the region, the United States should be doing more to ensure Ukraine can defend its borders."

Russia annexed Crimea in March 2014 and has continued to supply troops and weapons to pro-Russian rebels in eastern Ukraine, something Moscow denies it is doing, despite documented allegations by Western governments. The subject of lethal aid was publicly discussed in the days leading up to the signing of the Minsk II agreement in February this year, but the idea was rejected by Obama after discussions with German Chancellor Angela Merkel.

Since the ceasefire went into effect, few days have passed without actual fighting, and in recent weeks fighting has intensified. On Tuesday, eight soldiers were killed -- seven by a single blast from a land mine.

The increase in fighting and deaths has persuaded Congress, which has long been a supporter of supplying weapons to Ukraine, that the country still needs more assistance. So far, the U.S. has given Ukraine around $200 million in nonlethal aid such as bulletproof vests, helmets, sleeping bags and military training. 

"At today’s meeting, Prime Minister Yatsenyuk made it clear that increased military aid, defensive weapons and economic support will help Ukraine in its struggle for freedom and sovereignty," said Durbin. "The United States must act swiftly to provide this assistance, and the Senate Ukraine Caucus stands ready to help."

But polling says that a majority of citizens in NATO's biggest member nations agree with Obama. A recent Pew research poll, which asked respondents if they thought Ukraine should receive arms supplies, was taken in Great Britain, Germany, Spain, Italy, Canada, Poland, the United States and France. An average of 59 percent said they did not think Ukraine should get weapons. In the U.S., 46 percent of those polled said Ukraine should receive arms, whereas the more cautious Germans polled at just 19 percent in favor.