Viņķele, Čigāne and four other MPs form an unofficial 'liberal wing' within the party.
Zigfrīda Ozoliņa, the head of the Nereta Unity branch, told Latvian Radio that they decided last week to ask for the removal of Čigāne and Viņķele as the MPs had repeatedly violated party protocol.
Complaints over the MPs were also received from the Rēzekne branch and some party members in Rīga.
Unofficial sources say the reason for the complaints was that the two MPs met the Greens faction before the president came out with a PM nomination.
Party leader Solvita Āboltiņa told the media after the board meeting Monday that the decision on expelling the MPs was "delegated to the Ethics committee so we could return to reviewing the matter later."
While Viņķele told Latvian Radio she and Čigāne were pressured to leave the party during the meeting.
"A part of the board in no uncertain terms tried to show that perhaps elements like me and Lolita [Čigāne] have no place in the friendly Unity collective," Ilze Viņķele told Latvian Radio Tuesday.
Viņķele suggested that the other MPs from the liberal wing would join them if they were to leave. "We have decided that we're together," she said.
In that case, if push comes to shove Unity's 23 parliamentary seats would become 17, the same as National Alliance.
She also said, however, that recovery within the party is still possible, and she'll remain an Unity member while there's hope left.
There is no information on when the decision over expelling the MPs will be made.
Meanwhile, Unity announced an extraordinary congress to be held on October 29.
As Prime Minister Laimdota Straujuma (Unity) resigned on December 7, divides became apparent within the party as it could not nominate a candidate to push for the post of Prime Minister.
During the time, Viņķele and Čigāne held talks with the Greens and Farmers Union separately from the rest of Unity, which ultimately lost the premiership following an inside power-battle.