He said Singh, a former Union minister who had held various important portfolios at the Centre, should have "broad shoulders" to take no offence after having been sent to Parliament nine times in the past.
"It is unfortunate that the party could not accommodate him because of various winnability considerations in the seat. He is a very senior member and he should have realised this.
"And after realising this, after all the party has sent him to Parliament nine times, if he had to wait this time, here is nothing wrong in it," he told PTI when asked about Singh contesting the elections as an Independent from Barmer.
Singh has also been attacking the leadership including Narendra Modi ever since the denial of ticket last week.
"People are too clever that they can see where the party is wrong and where the party is correct. I think in this case the individual concerned has over reacted.
"I think ambition has to be seen with loyalty and I passed that test. I am not sure whether I can say that about some others. I think, he is overreacting," Jaitley said.
He was reacting to a question on Singh's remarks that "Jaitley is not an example of lacking ambitions. His aspirations are punishing."
"If for 34 years, nine times you are sent into Parliament. I am sure, you should have the broad shoulders to take no once. I am not for the moment saying that. There is a lot of space for seniors to guide the party," Jaitley said.
About the controversy over the candidature of senior leaders L K Advani and Murli Manohar Joshi, he said "the episodes of Dr Joshi and Advaniji are only in the media and in party there was no such real episode."
'There is no BJP; it's only Modi, Modi and Modi'
'Mirchi girl' Rakhi Sawant wants to spice up LS polls in Mumbai
Sheela Says: Modi's Varanasi blues
Antony, Kejriwal are Pak agents, India's enemies: Narendra Modi
No chance of a united candidate against Modi in Varanasi