World leaders have attended a donor conference in London with an urgent plea for billions of dollars in aid for refugees from war-torn Syria who face worsening conditions and diminishing peace prospects.

The Feb. 4 conference was overshadowed by the suspension of peace talks in Geneva the day before, and intense fighting on the ground in Sryia.

A Syrian government offensive, backed by Russian air strikes, is continuing north of Aleppo, the BBC reported.

The European Union and its member States said they pledged more than €3 billion ($3.4 billion) to assist the people inside Syria as well as refugees and the communities hosting them in the neighboring countries for the year 2016.

The EU said the crisis emanating from the war in Syria is "the worst humanitarian crisis since World War II."

"There is a critical shortfall in life-saving aid," said UK Prime Minister David Cameron.

Germany pledged $2.6bn (£1.9bn; €2.3bn) and the UK $1.7bn in new refugee aid.

Turkish Prime Minister Ahmet Davutoglu said an estimated 70,000 Syrians fleeing the bombing were moving towards Turkey.

The Lutheran World Federation said that a lack of education, protection, and assistance with livelihoods are the most pressing needs of Syrian refugees.

A call to action by the LWF and 41 humanitarian organizations who are assisting refugees from Syria urged donors to put extra funding into these areas.

The paper was published to coincide with Supporting Syria and the region conference on Feb. 4 in London

"Warring parties continue to violate UN Security Council resolutions and international humanitarian law by deliberately and wantonly attacking civilians and civilian infrastructure, including homes, markets, schools and hospitals" the paper reads.

Having exhausted their financial reserves, a lack of funding forces refugees to "accept exploitative work, driving impoverished parents to send their children into exploitative child labor," said the LWF paper.

The situation forces "desperate women and girls into survival sex and early marriage, and leading men, women and children to return to Syria, or try to reach Europe through informal channels, at great risk to their lives," the paper explains.

The 42 non-governmental organizations behind the paper include the church aid groups such as the LWF, Christian Aid, Cafod International, Caritas Germany, Tearfund and World Vision as well as Save the Children.

Among their proposals they said:

"We urge donors to ensure that investments in livelihoods benefit host communities and other refugee communities, including Palestinians, as well as Syrian refugees to enable social cohesion.

"This should also include a thorough market analysis to understand the labor markets in host countries," they said.