Death toll mounts in east Ukraine as US mulls arming Kiev

Fears grew Tuesday of an escalation in the mounting bloodshed in east Ukraine as the United States mulled arming Kiev and pro-Russian rebels ordered a mass mobilisation.
At least 16 civilians and five government troops were killed over the past 24 hours in fierce clashes across the conflict zone, government and pro-Russian rebel officials said.
The ferocious fighting remains focused around the battleground town of Debaltseve, a strategic railway hub between the rebel strongholds Donetsk and Lugansk where separatists are fighting to encircle Ukrainian forces.
- US mulls arms supplies -
The latest casualties come as fighting has surged in recent weeks after separatists tore up a tenuous ceasefire deal and pushed into government-held territory.
The United Nations said Tuesday the civilian death toll has risen by 224 in the past three weeks and that the total of those killed in the conflict since April now stands at over 5,358 people.  
"Any further escalation will prove catastrophic for the 5.2 million people living in the midst of conflict in eastern Ukraine," warned UN High Commissioner for Human Rights Zeid Ra'ad Al Hussein.
Concerns over the spiralling conflict come as Washington says it is seriously considering providing arms and more military equipment to Ukraine.
President Barak Obama's administration had previously ruled out sending weapons to Ukraine's government but the failure of economic sanctions to force Russia to halt alleged military support for the separatists has prompted a second look at the option, officials told AFP.
"What's being discussed is perhaps we should begin providing defensive weapons,defensive equipment, to Ukraine," a senior official said.
Washington so far has provided non-lethal assistance to Ukraine, including flak jackets, medical supplies, radios and night-vision goggles.
US Secretary of State John Kerry is to jet into Kiev on Thursday for meetings with President Petro Poroshenko and Prime Minister Arseniy Yatsenyuk but no official announcement on weapons deliveries is expected.
A Ukrainian diplomatic source told AFP that Kiev was hoping to get more "clarity" on its request for weapons following Kerry's visit and a raft of high-level meetings at an upcoming security conference in Munich.
- Rebels want 100,000 fighters -
Ukraine and its Western allies accuse Moscow of sending thousands of regular army troops and weapons to support the rebels and spearhead their latest offensive.
Moscow has repeatedly denied the allegations but the rebels, however, appear to be equipped with the heavy weaponry of a regular army.
As rebels continued to push their offensive, their leaders have announced a mass mobilisation aimed at boosting fighter numbers to 100,000.
The voluntary call-up -- which has been met with scepticism by some in rebel-held territory -- is set to start next Monday, insurgent leader Alexander Zakharchenko said.
Kiev authorities announced at the end of January that they also were calling up 50,000 troops in the face of the latest rebel offensive.
Hopes of defusing the conflict look more distant than ever after the latest attempt at truce talks collapsed in acrimony in the Belarussian capital Minsk over the weekend.
The rebels say they are willing to stop fighting only if Kiev agrees to redraw the demarcation line agreed in a September ceasefire deal to include gains they have made since in recent days.
In the meantime, life for civilians trapped in the crossfire continues to deteriorate rapidly, with many fleeing.  
"The situation is getting worse by the day," the head of the International Committee of the Red Cross in Ukraine, Michel Masson, said in a statement.
"People are hiding in basements for days on end and those who dare to venture out to collect basic aid risk being wounded or killed."