As increased fighting on the ground in eastern Ukraine threatens the already fragile ceasefire, members of the U.S. Congress once again are pressing President Barack Obama to request lethal military aid for Ukraine to combat Russian-backed rebels. The president already has ignored a resolution urging lethal U.S. aid for Ukraine that the House passed by 348 to 48 votes.

"There is no doubt that it is important to provide humanitarian assistance to the population that is affected by the fighting. However, this aid only treats the symptoms of a larger problem," read the statement by Reps. Michael Fitzpatrick, R-Pa., Sander Levin, D-Mich., and Marcy Kaptur, D-Ohio. "The Ukrainian government is in dire need of defensive weapons, which are necessary to protect its borders and sovereignty.”

“The defensive items will help Ukraine to continue the process of economic and government reforms initiated after the Euromaidan," it added, referring to the revolution that ousted pro-Russian President Viktor Yanukovych last year.

Obama and German Chancellor Angela Merkel agreed during Merkel's recent visit to Washington that supplying American, or European, weapons would only lead to more bloodshed. The U.S. and European Union are still supporting the Minsk II agreement, which was signed Feb. 12 and prescribed a ceasefire that came into force on Feb. 15, although that truce has been broken almost daily since then.

But over the last three weeks, fighting has increased around the port city of Mariupol and the pro-Russian rebels' de facto capital of Donetsk. The Organization for Security and Cooperation in Europe, the group charged with overseeing the ceasefire, reported last week that more than 1,100 explosion were noted in Donetsk, and hundreds of instances of shelling in a village close to Mariupol, although it could not say which side was firing.

A series of local ceasefires brokered by the OSCE have also failed in various locations around the country.

Last week, Democratic presidential candidate Hillary Clinton said Ukraine deserved more support than the U.S. has provided so far. Defense Secretary Ashton Carter has also indicated he is in favor of providing the Ukrainian army with weapons.