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LAUSANNE, Switzerland, March 18 (Reuters) - Iran's foreign ministry said on Wednesday it saw no difference between Israel's political parties and called them all aggressors, semi-official Mehr News Agency reported after Israeli Prime Minister Benjamin Netanyahu's election victory.

Netanyahu, whose Likud party unexpectedly won Israeli elections on Tuesday, warned U.S. President Barack Obama's administration this month that it was negotiating a "bad deal" with Iran over its nuclear programme.

The United States and its allies suspect Iran of seeking nuclear weapons capability. Tehran says its nuclear programme is purely for peaceful purposes, but Israel regards it as a threat to its existence and refuses to rule out military action.

"For us there is no difference between the Zionist regime's political parties. They are all aggressors in nature," Iran's foreign ministry spokeswoman Marizeh Afkham told reporters at a weekly news conference in Tehran, Mehr reported.

Since its 1979 Islamic revolution, Iran refuses to recognise Israel.

U.S. Secretary of State John Kerry declined to comment on the Israel election when asked by reporters on the sidelines of nuclear talks with Iran in Lausanne, Switzerland. (Reporting By Parisa Hafezi and Lesley Wroughton; Writing by John Irish; Editing by Andrew Heavens)