The United States took the "unusual step" of sharing highly classified intelligence data on Iran's alleged efforts to develop a nuclear-capable missile to secure India's support for the International Atomic Energy Agency resolution against Tehran's controversial atomic programme, an American expert has claimed.

• The Iran vote and after

The maturity of the deepening Indo-US relationship is being tested by the contentious issue of Iran and Washington
was "pleased and relieved" that New Delhi finally backed it in taking a tough stance in dealing with Tehran, John E Carbaugh, a policy analyst who advises the US administration and major American multinational firms, said in his latest India Report.

To secure the Indian vote, claimed Carbaugh, the US took the "unusual step" of sharing highly classified intelligence data on Tehran's alleged efforts to develop a missile capable of delivering a nuclear warhead.