"We continue to work directly with the [Lebanese] government," Crowley said. "[We] have strong suspicions about the motives of Iran and its - you know, the groups that it supports who do not have Lebanon's long-term interest at heart."
Crowley expressed concern about the prospect of Iran providing arms to Lebanon.
"A challenge for Lebanon is the fact that you have outside players who are providing military capabilities to sub-state groups such as Hezbollah," he said. "So we would naturally have concern that the provision of any arms into Lebanon would not be for the benefit of the national government, it would be to strengthen groups like Hezbollah, which both undermine the sovereignty of Lebanon itself but also pose a tremendous security risk to the region as a whole."
On reports of possible meeting on Friday in Lebanon between Ahmadinejad and Turkish Prime Minister Recep Tayyip Erdogan, Crowley said Turkey has been an effective interlocutor with Iran.
"If such a meeting takes place at the end of the week, we would hope that [Erdogan] would continue to deliver that strong message that Iran, having been a less than constructive player in the region, should change directions and more broadly should engage the international community on the range of issues and concerns that we have, not the least of which is the true nature of its nuclear program," Crowley said.
Ahmadinejad arrived in Lebanon on Wednesday on his first state visit to the country. The Iranian president met with Lebanese leaders and addressed a huge rally in a Hezbollah-controlled neighborhood in southern Beirut.
Ahmadinejad reportedly met with Hezbollah leader Hassan Nasrallah before the rally and Nasrallah delivered remarks at the rally via video link in which he thanked Ahmadinejad for his support.