Facing trouble from their candidates who are now refusing to withdraw from the polls, the Congress and the SP on Tuesday cracked the whip and asked the candidates to immediately pull out from the race where the alliance has declared joint candidates.

Samajwadi Party's (SP) state unit chief Naresh Uttam issued a statement asking its candidates from Maharajpur (Aruna Tomar), Kanpur Cantt (Mohd Hasan Rumi), Koraon (Ramdev Kol), Bara (Ajay Kumar 'Amritlal') and Mahrauni (Ramesh Kumar) to immediately withdraw their nominations and pave way for the Congress candidates.

On Monday, some candidates had refused to toe the party line.

Similarly, Congress Rajya Sabha member Rajeev Shukla has asked Maroof Khan from Lucknow Central, Abhumanyu Singh from Bindki, Jawahar Lal Diwakar from Soraon, Bhagatram Mishra from Prayagpur and Bhagauti Chowdhary from Chanve to pull out.

Maroof Khan openly rebelled against the party diktat late on Monday, saying at this juncture it is impossible for him to do so.

"I have campaigned so extensively, my supporters have worked so hard and I am getting a lot of support from my supporters... there is no way that I am withdrawing," he told reporters.

On over a dozen seats, including in Amethi -- the Gandhi pocket borough, the two parties have not been able to thrash out the contentious issues relating to ticket distribution.

Anger and discontent is simmering in the rank and file of both parties, something which does not augur well for the party at this stage.

Lucknow and neighbouring areas will vote on February 19.