Looming security choices over Iran’s nuclear ambitions and Russian power politics with energy supplies pose new challenges to transatlantic relations that are still recovering from a deep crisis over Iraq.

These were the dominant themes of a weekend Brussels Forum of political, business and opinion leaders from Europe and North America convened to thrash out the toughest issues.

The United States and European Union countries are working together again on troublespots from Afghanistan to Gaza, but potential new divisions lurk over the use of force against Iran and to stop the killing in the Sudanese province of Darfur.

While EU foreign policy chief Javier Solana insisted US-European cooperation was now “almost perfect”, differences of tone and intention were clearest on Iran.

Few European speakers agreed with Republican Senator John McCain’s statement that: “The one thing worse than military action would be a nuclear-armed Iran.”

Solana said no one had mentioned military options at a meeting of NATO and EU foreign ministers, including US Secretary of State Condoleezza Rice, and Europeans did not want to join a “coalition of the willing” against Iran.

US speakers from both parties said isolating and imposing sanctions on Tehran would be the litmus test of transatlantic relations. McCain warned Russia and China of a congressional backlash if they blocked UN action against Tehran.

While Democratic presidential hopeful John Edwards said the United States should engage Iran in direct talks, other US participants suggested Washington could not talk to a president who denied the Holocaust and called for Israel’s destruction.

The Americans, led by McCain, a potential Republican presidential candidate, voiced impatience at perceived European reluctance to intervene militarily to halt what Washington has branded genocide in Darfur.

They did not suggest sending US troops to the conflict, in which at least 180,000 people have died and more than two million have fled their homes, according to UN estimates.

When Solana and NATO Secretary-General Jaap de Hoop Scheffer said they could not act without an agreed “political framework”, former assistant secretary of state Richard Holbrooke called it “buck-passing” and “bureaucratic words while people are dying”.

Europeans and North Americans agreed in their assessment that Russian President Vladimir Putin was trying to use gas pipelines for political coercion and vowed to resist.

European Commission President Jose Manuel Barroso, US Assistant Secretary of State Daniel Fried and Canadian Foreign Minister Peter McKay said they would press Putin at a summit in July to open Russia’s energy markets in return for reciprocal access to the West.

Some speakers warned against starting a new Cold War over energy, while others called for a firmer line towards Putin’s “semi-democracy” (Barroso) and “perverted vision of a restoration of the Soviet empire” (McCain).

Deep differences between Poland and Germany over a planned undersea Russian gas pipeline highlighted the difficulty of building a common European energy policy.

Polish Defence Minister Radek Sikorski compared the direct Baltic Sea pipeline, bypassing Poland and Belarus, to the notorious 1939 pact between Nazi Germany and the Soviet Union.

“Poland has a particular sensitivity to corridors and deals above our head. That was the Locarno tradition, that was the Molotov-Ribbentrop tradition. That was the 20th century. We don’t want any repetition of that,” he told reporters.

On other issues on the transatlantic agenda, the Americans urged enlargement-weary Europeans not to turn their back on admitting the Western Balkans and eventually Turkey to the EU. And both sides agonised inconclusively over how to manage China’s emergence as a world power, balancing economic opportunities with concerns about democracy and human rights. Craig Kennedy, president of the German Marshall Fund of the United States, the lead organiser of the $900,000 event, said he hoped the Brussels Forum would become a regular fixture for transatlantic dialogue. There will be no shortage of issues. — Reuters