US President Barack Obama has proposed to "deepen" military cooperation between the US and Russia against some Syrian armed groups in exchange for Russia putting a stop to the bombing of US-backed rebels, according to a report.
The US sent the agreement's text to Russia on Monday after several weeks of negotiations, a member of the Obama administration told The Washington Post on Thursday.
The alleged deal stipulates that the US will primarily join forces with Russia to target and strike the al-Nusra Front armed group, the Syrian affiliate of al-Qaeda.
On the other hand, Russia will also pressure the government of Syrian President Bashar al-Assad to halt its bombing of armed rebel groups supported by the US, The Washington Post added.
The report comes at a time when casualties from Russian air strikes continue to mount.
Of the 7,031 people killed by Russian air strikes in Syria throughout the past nine months, more than 35 percent of them (2,498) were civilians, according to a press release published on Thursday by the Britain-based Syrian Observatory for Human Rights.
Among the civilians, at least 587 were children and 360 women.
The Syrian uprising started with largely unarmed demonstrations against the Assad government in March 2011, but has since become a full-on civil war between the Assad government and rebel forces.
More than 270,000 people have been killed throughout five years, according to the Observatory's statistics.
Efforts to reach a peace agreement have fallen through time and again. United Nations special envoy to Syria Staffan de Mistura said on Thursday he aims to restart intra-Syrian negotiations in July and reach a political transition by August.
"What we need is that the stakeholders do come with a feeling of urgency and work on some ideas on how to bridge the differences between what everyone means by political transition," de Mistura said.
Source: Al Jazeera