Syrian government troops who have besieged dozens of rebel-held communities are moving toward their biggest target yet — the opposition-controlled neighborhoods of the city of Aleppo, where some 300,000 people risk being trapped.

Sieges were widely used for centuries as a military tool — from Jerusalem to Leningrad and Sarajevo — and aren't defined outright as a war crime. However, recent images of emaciated civilians in blockaded areas, such as the Syrian town of Madaya, have prompted global outrage.

Syria's Kurds, long held in disdain by Damascus, are edging towards autonomy in their heartland along Turkey's border as they capitalize on the tactical goals of both Washington and Moscow.

To the dismay of Ankara, Kurdish forces have seized on the collapse of rebels in the northern province of Aleppo in the face of Russian-backed regime gains to advance to within 20 kilometers (12 miles) of the border.

Turkey and Russia are already waging a proxy war in Syria as Istanbul backs rebels against Syrian government troops supported by Moscow. 

But the recent escalation in rhetoric has sharpened fears of a direct confrontation, analysts warn.

Arseniy Yatsenyuk once said that taking the job of Ukrainian prime minister was an act of "political suicide" and on Tuesday he appeared to have been proved right.

Facing charges he has been unable to deliver on a pledge to tackle corruption and fix the economy, the bespectacled pro-Western premier was asked to step down by the president "in order to restore trust in the government".

Five years after the uprising began against dictator Moammer Gadhafi, many Libyans have lost hope of seeing the rule of law return to a divided country threatened by jihadist expansion.

The Islamic State (IS) group has exploited the chaos engulfing the oil-rich North African nation since the 2011 revolution to gain a foothold and expand its influence.

Ehud Olmert was once described as "probably the best" politician Israel had ever produced, but the debonair ex-premier who began a prison term for corruption on Monday has seen a humiliating fall from grace.

Olmert, 70, became Israel's first ex-prime minister to serve jail time when he walked into the Maasiyahu prison in the central city of Ramle for the 19-month term.

After months of tensions, Turkey is taking on Syrian Kurdish fighters inside Syria in a move that risks inflaming tensions with its NATO ally the United States and complicating the search for peace after almost five years of civil war.

On consecutive days this weekend, Turkish forces struck positions of Syrian Kurds with fire from Firtina howitzers deployed on the border, saying the army responded to incoming attacks. 

Syrian Amir al-Halabi is once again alone this Valentine's Day, separated from his sweetheart by the war that has left the lovers on opposite sides of the divided city of Aleppo.

Halabi, 20, is a photojournalist living in the rebel-held east of Aleppo city, a once-thriving economic hub that has been devastated by Syria's conflict that began in March 2011.

Agence France-Presse has launched a weekly series of reporters' blogs taking readers behind the scenes of the 2016 U.S. election for a look at the events and attitudes shaping the White House race.

The third post in the series comes from New Hampshire, the Granite State, which held its presidential primaries on February 9, won by Democratic White House hopeful Bernie Sanders and Republican frontrunner Donald Trump:

World powers on Friday agreed a plan to cease hostilities in war-wracked Syria, but there are reasons to doubt its success.

Here are the key questions around the deal: