President Obama has decided to dispatch an ambassador to Syria, ending a four-year freeze in relations with a country that may represent his best chance of making early progress on faltering Middle East peace negotiations.

The State Department said yesterday that an ambassador would return to Damascus for the first time since 2005 but added that it was likely to be several days before a formal nomination was sent to the Senate for confirmation.

“This decision reflects the Administration’s recognition of the important role Syria plays in the region and our hope that the Syrian Government will play a constructive role to promote peace and stability in the region,” an official said.

The Bush Administration withdrew the last US ambassador in protest at alleged Syrian links with the assassination of Rafik Hariri, the former Prime Minister of Lebanon. Since then a chargé d’affaires has been the highest-ranking US diplomat in Damascus.

Mr Obama promised a diplomatic offensive across the Middle East and argued that the policy of isolating America’s enemies has served only to create a vacuum that has been filled, to some extent, by Iran. Prospects of direct negotiations with Tehran have, however, diminished after the crackdown on street demonstrations. Although Mr Obama has left the door ajar to talks over Iran’s nuclear programme he used a White House press conference this week to suggest that the regime’s handling of the protests “may end up colouring” its relationship with the rest of the world.

The President has set a tight diplomatic timetable to assess whether talks will serve any purpose, saying last month that he should know Iran’s intentions over its nuclear programme by the end of the year. Russia has already broken with the West by recognising the re-election of Mahmoud Ahmadinejad, and Washington is caught in a dilemma over whether any negotiations would be seen as further legitimising the Iranian regime.

Similarly, hopes of a breakthrough in securing a Palestinian peace settlement have hit rough terrain with Benjamin Netanyahu, the Israeli Prime Minister, yesterday postponing a planned meeting with George Mitchell, Mr Obama’s envoy in the region, because of divergent views over Jewish settlements in the West Bank. Overtures to Syria, by contrast, have received a warmer response. A series of visits to Damascus by high-ranking US officials over recent weeks, including one by Mr Mitchell this month, were regarded as productive.

Improved relations with the US could mean a lifting of sanctions and new business deals — something many Syrians yearn for. Damascus promised to reopen an American cultural centre that was closed after a US raid last year into its territory against suspected al-Qaeda militants.

After his talks with President Assad of Syria, Mr Mitchell highlighted his host’s integral role in securing peace in the Middle East. Washington has asked Syria repeatedly to deny access to foreign fighters trying to cross the border into neighbouring Iraq and hopes to unpick its close relationship with Iran. The countries have a mutual defence treaty and provide support to Hezbollah, which the US branded a terrorist organisation.

Mr Assad is seen as holding at least one key to unlocking the Arab-Israeli peace process. Hamas and Islamic Jihad — armed Palestinian movements that do not recognise Israel’s right to exist — maintain political offices in Damascus and Israel has occupied the Golan Heights since the Six-Day War. In recent years Israel and Syria, which never signed a peace deal after the war 42 years ago, have been exploring a settlement.

Yesterday however Mr Assad indicated that the return of the occupied territory must be a pre-condition of formal negotiations. “Achieving peace requires an Israeli partner and commitment to international law, United Nations resolutions and the land for peace principles,” he said. “This Israeli partner does not currently exist.”

Mr Obama has spoken of the need to secure a region-wide settlement by pursuing all opportunities for progress, which includes a rapprochement with Damascus. As such, his new ambassador to Syria is likely to be a professional diplomat with experience of the tinderbox politics of the Middle East.

His nominations for the ambassador post in Europe, by contrast, have been dominated by campaign donors and friends — reflecting what appears to be the relatively low importance that the White House attaches to relations with old allies.

Of 13 ambassadors nominated to Europe six raised six-figure sums for Mr Obama’s election fund, including Louis Susman, who is lined up for the post in London.

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