Vienna: The UN nuclear watchdog's head Yukiya Amano suggested before he took office last year he was "solidly in the US court" on key issues including Iran, US diplomatic cables cited by the Guardian newspaper said.
The revelation may add to tension between Amano, who is the International Atomic Energy Agency's (IAEA) Director-General, and Iran at a sensitive time in world diplomacy over the Islamic state's disputed nuclear programme.
Throwing independent weight behind the West's suspicions, Amano said in his first report on Iran in February that the IAEA feared Tehran may be working now to develop a nuclear-armed missile.
Iran has accused Amano, a veteran Japanese diplomat, of bias and relations soured further in June when he said Tehran was hampering the agency's work by barring some of its inspectors.
After Amano was narrowly elected by IAEA member states in July last year but before he took office in December 2009, the US mission in Vienna described him in a cable as a "DG [Director General] of all states, but in agreement with us".
It said Amano had reminded the US ambassador on several occasions that he would need to make concessions to developing countries, "but that he was solidly in the US court on every key strategic decision, from high-level personnel appointments to the handling of Iran's alleged nuclear weapons program."
Amano, who succeeded Nobel Peace laureate Mohammad Al Baradei, was elected to the position thanks to overwhelming support from industrialised states while many developing countries regarded him as a poor communicator and a tool of Western powers.
Another cable cited by the Guardian said a meeting with Amano had illustrated "the very high degree of convergence between his priorities and our own agenda at the IAEA".
The cables also suggested there were staff tensions within the Vienna-based agency, with one quoting Amano as saying he was seeking to replace a senior official with someone who was closer to his own thinking. The official named in the cable is still in his position.
The IAEA and the US mission were not immediately available to comment on the report.