Washington, Sep 18 (Xinhua) US Secretary of State Hillary Clinton said Friday that Iran's defiance on the nuclear issue would lead to 'more isolation and economic pressure'.

'There will be accompanying costs for Iran's continued defiance: more isolation and economic pressure, less possibility of progress for the people of Iran,' she said in a speech at the Brookings Institution, a think-tank based in Washington.

'We have made clear our desire to resolve issues with Iran diplomatically. Iran must now decide whether to join us in this effort,' she said.