Yitzhak Herzog, Tzipi Livni
Yitzhak Herzog, Tzipi LivniYossi Zeliger/Flash 90

Reports on Friday indicated a rapidly forming coalition between Opposition and Labor party chairman Yitzhak Herzog and Hatnua chairperson Tzipi Livni, in which the two would likely form a joint list - with Kadima possibly joining along for the ride.

According to Walla!, Herzog and Yesh Atid chairman Yair Lapid are competing to bring Livni into their parties in a bid to become the largest in the "center-left" bloc as it is being referred to.

However, it appears that Livni is leaning towards Herzog, with senior Labor party sources telling the paper there is a plan for Livni to have the second spot on the joint list reserved for her, and two other spots in the first ten reserved for MKs Amram Mitzna and Amir Peretz.

The Labor sources said the plan "has a 60% chance."

According to a poll this week conducted by the Rafi Smith Institute for Globes, if Livni and Herzog were to run together they could expect to get 24 seats and become the largest party, outstripping Likud by one mandate.

A third wheel in the plan would be incorporating MK Shaul Mofaz's Kadima party into the list. The Labor sources explained "we don't have a security expert and Mofaz would fit," adding he would have a reserved spot in the top ten.

"But first of all we'll wait to see if Livni is coming. Without her it isn't relevant," added the source.

Mofaz, whose Kadima party was formed by former Prime Minister Ariel Sharon to force through his 2005 Disengagement plan from Gaza, is the sole Kadima MK in the Knesset. Backing up the assessment of an impending union, Makor Rishon reported on Friday he may be joining Labor after meetings with Herzog.

Providing further confirming evidence of the negotiations between Livni and Herzog, the two took off in a shared plane to Washington DC on Thursday night to take part in the Saban Forum.

At Ben Gurion International Airport the two sat together, and Herzog even put a picture of the two on his Facebook.

A source close to Herzog used his nickname, saying "Buji is in the clouds, and I don't mean the plane."