AMID tentative signs that the two kidnapped Syrian archbishops are safe and in good health, the international community has begun what looks like a final attempt to find a diplomatic solution to the worsening crisis in Syria.

Nothing has yet been heard directly from the Syriac Orthodox and Greek Orthodox Archbishops of Aleppo, Mor Yohanna Ibrahim, and the Most Revd Paul Yazigi, who were seized last month (News, 3, 10 May).

But a prominent Lebanese Christian leader, Amin Gemayel, has reported receiving assurances from the acting head of the Syrian National Council opposition group, George Sabra, that the two men are in good health. They are apparently being held by a group of rebels near Aleppo.

Mr Gemayel announced the news after a meeting with Metropolitan Theophilos George Saliba, of Mount Lebanon; Bishop Daniel Koriyeh, of Beirut; the President of the Syriac League, Habib Afram; and the Deputy Bishop of Aleppo, the Very Revd Joseph Shabo. The group did not specify what steps were being taken to secure their release.

Meanwhile, diplomatic efforts to try to end the fighting in Syria have gathered momentum. After a joint call last week by the United States and Russia for an international conference on Syria to be convened in early June, David Cameron held talks in Russia with President Putin. He then flew to Washington for discussions with President Obama.

There is no mistaking the determination of the leaders involved, but President Obama said: "I'm not promising that it's going to be successful. It's going to be challenging, but it's worth the effort."

The obstacles in the way of progress are huge. Although Russia agrees with Western states that a diplomatic initiative is required, differences remain. Moscow insists that Syria has a future under President Bashar al-Assad.

Also, it is uncertain who would represent the various factions that comprise the Syrian opposition at an international conference. Furthermore, there must be doubts whether President Assad would agree to participate in a meeting that would effectively require him to hand over power.

Summing up the prospects of the coming weeks, President Obama was not optimistic. "Sometimes, once the furies have been unleashed in a situation like we're seeing in Syria, it's very hard to put things back together.

"There are going to be enormous challenges in getting a credible process going, even if Russia is involved, because we still have other countries like Iran. And we have non-state actors, like Hezbollah, that have been actively involved."