Washington would never make a deal with Syria that would harm Lebanese interests, U.S. Secretary of State Hillary Clinton said during a previously unannounced visit to Lebanon on Sunday.

Clinton's three-hour stop in the Lebanese capital of Beirut came seven weeks ahead of a critical general election in Lebanon.

Clinton said U.S. attempts to engage Syria and Iran are not being done at the expense of American support for Lebanon.

"There is nothing that we would do in any way that would undermine Lebanon's sovereignty," Clinton said.

The June 7 election pits a pro-Western coalition against an alliance led by the militant group Hezbollah and backed by Syria and Iran.

Syria dominated Lebanon for nearly three decades before it was forced to withdraw its tens of thousands of troops four years ago this week in the wake of the assassination of former prime minister Rafik Hariri.

During her visit, Clinton met President Michel Suleiman and laid a wreath at Hariri's grave.

A United Nations investigation implicated Syrian security officials in Hariri's assassination, but Damascus has denied involvement.

Clinton said the elections should be free from violence and fear, and the Lebanese people should be able "to choose their representatives through transparent elections away from foreign influence."

She would not speculate on the results of the election and what the U.S. would do if Hezbollah wins.

With files from The Associated Press