Catherine Ashton in landmark bridge-building trip to Iran
The difficult and delicate process of forging a new relationship between Iran and the West takes another step this weekend with the first visit of Europe's foreign policy chief, Catherine Ashton, to the Islamic Republic.
It will also be a significant challenge for Baroness Ashton as she seeks to build on recent foreign policy successes to broach critical issues ranging from human rights to Tehran's role in regional conflicts including Syria.
On Saturday morning Iranian newspapers, of a more reformist leaning, welcomed her mission, hailing it as an achievement of Iranian President Hassan Rouhani's new approach.
Coverage of her visit, across moderate and hardline media, will underline both the centrality and sensitivity of her role here.
Mrs Ashton has been widely credited with playing a key role in negotiating the landmark interim deal between Iran and world powers last November, which requires Tehran to curb its nuclear programme in exchange for limited relief from sanctions.
Syria crisis: A Palestinian plea from Yarmouk refugee camp
"Please, please take us out, we are dying here," 60-year-old Wafiqa pleads, sobbing uncontrollably as she cradles her lined face in rough gnarled hands.
She stumbles toward us in her grief, toward anyone she thinks can rescue her from the punishing eight-month siege of Yarmouk, a devastated Palestinian refugee camp south of Damascus.
Just behind her, a tide of hundreds of people presses against a security barrier. Armed men struggle to contain a crowd desperate to reach a UN food distribution point at the end of a narrow rutted road that cuts through a desolate wasteland of utter ruin.
"I'm so tired, so tired," one woman cries out.
It was as if she was a self-appointed spokesperson for the suffering.
Syria open to dialogue, but on its terms
While all eyes are on the crisis unfolding in Ukraine, a solution also still seems a long way away in the Syrian conflict.
When the recent peace talks collapsed in Geneva, the United States, France and Britain blamed the Syrian government, accusing it of blocking any chance of establishing a transitional government.
The second round of talks ended on 15 February with UN envoy Lakhdar Brahimi saying no progress had been made.
One key stumbling block was the actual agenda of the talks. Should discussions focus on the short term - ending the violence? Or the long term: putting a new government in place?
The opposition has made it clear that it wants President Bashar al-Assad to resign, but the Syrian authorities say there is no question of replacing him.
Homs evacuees: Anxious young men from a besieged Old City
We didn't recognize the men we'd met just a few days earlier when they emerged from the rebel-held Old Quarter of Homs.
Their ragged beards are trimmed or shaved. They have new clean clothes.
But they still wear the hunted look of anxious men as they wait for their cases to be decided in the city's al-Andalus school that is now both shelter and screening centre.
And the memory of the painful life they escaped in the besieged Old City still haunts them.
"Families were ready to kill for food," Youssef tells us, as nine-year-old Mariam throws all the loving weight of her little arm around her big brother. He's now been re-united with family members who are able to visit him here.
Syria conflict: Emerging from the siege of Homs
The first to arrive couldn't walk.
They hobbled on crutches, lay moaning on stretchers, or were gently eased into wheelchairs from white armoured vehicles with blue UN flags.
It was a first sad glimpse of lives lived under siege: the wounded who survived nearly two years under fire in the Old City of Homs; the elderly, bent by anguish and age, in need of medicine, comfort, and care.
Then the buses pulled up, curtains drawn, outside the abandoned white banqueting hall transformed into a makeshift reception centre for people escaping the rebel-held Old City under a temporary truce.
Each driver paused, engine still running, until a human cordon formed outside, of young red-vested volunteers of the Syrian Arab Red Crescent Society.
Syria conflict: Aid and evacuations continue in Homs
The "humanitarian pause" in the Old City of Homs is a rare glimmer of light in a dark and devastating war. The UN says the mission has already helped a "significant" number of people to leave the besieged area and a "limited" amount of aid is getting through.
The UN's resident humanitarian co-ordinator, Yacoub El Hillo, told me they were "baby steps" that, he hoped, could lead to the "giant steps" that were needed.
But a rare truce also meant to build trust is exposing deep enmities. The longer the mission goes on, the more sensitive it becomes.
Some pro-government forces are vehemently opposed to an operation that is allowing fighters to escape an area that has been the focus of heavy fighting for nearly two years. And the opposition is angry that young men who leave are being taken in for questioning.
More than 100 have been released, but more than 200 are still being held. In Syria's brutal conflict, even humanitarian pauses cannot escape the cruel logic of war.
Syrian peace talks: Small steps forward, big lurches backwards
"If peace cannot be brought, how can humanity be brought to the conduct of the war?"
That's how David Miliband, who heads the International Rescue Committee, recently phrased two pressing goals for Syria.
On Monday, as a second round of peace talks gets under way in Geneva, both the worsening war and a grave humanitarian crisis will be on the agenda again.
For much of the first round, UN envoy Lakhdar Brahimi expressed anguish over the failure of warring sides to agree, at the very least, a humanitarian ceasefire in the embattled city of Homs.
Then, a few days after talks broke up, the UN announced a "humanitarian pause" had finally been reached between government and opposition forces.