Zionist Union leader Isaac Herzog on Thursday accused Prime Minister Benjamin Netanyahu of turning Israel into a partisan issue in US politics.Speaking at a press conference with his Zionist Union co-leader Tzipi Livni, Herzog took aim at Netanyahu for turning down an invite to meet with Senate Democrats while he is in Washington to address the Congress next week. "We recently heard very harsh language from senior US officials, but what most bothers me is that Netanyahu refused to meet with the Democrats," Herzog said.Netanyahu has faced criticism at home and abroad for his plans to address Congress on Iran's nuclear program on March 3, just two weeks before Israeli elections. He accepted the invitation from Republican leaders in the US Congress, who consulted neither Democrats in Congress nor Democratic President Barack Obama's administration.Netanyahu has increasingly come under fire in recent days from senior Obama Administration officials for his outspoken criticism of the deal emerging between Iran and the P5+1 group of world powers. "Netanyahu is playing politics at the expense of diplomacy," Herzog said. He called on Netanyahu to cancel his address to Congress. "If I was in your place, I wouldn't go there, I would hold intensive talks with the US president," Herzog said."The Iranian threat must be dealt with differently, he added.