Mr Basit, who was twice overlooked for the post of foreign secretary, made the harsh remarks in a letter - widely circulated on social media - dated July 5, 2017 and printed on his official letterhead while he still served as Pakistan's high commissioner in New Delhi.
The foreign office has not confirmed the authenticity of the letter. However, the Dawn news, which published the letter on its website, quoted its sources in the foreign office as saying that the letter is authentic.
"The more I think the more I am convinced that you have been the worst Foreign Secretary ever," Mr Basit wrote in response to a farewell letter by Mr Chaudhry which he sent to the former on March 12 after his appointment as the ambassador of Pakistan to Washington.
Instead of wishing him good luck on his new assignment, Mr Basit had an ominous warning in the letter: "My concern is that you would also end up being the worst Pakistan Ambassador in Washington D.C."
He asserted that Chaudhry was not made for the "delicate profession of diplomacy" and cited the Ufa joint statement with India and Pakistan's failure to get re-elected to the UN Human Rights Council as leading examples of his failures.
The joint statement issued after Prime Minister Narendra Modi and his then Pakistani counterpart Nawaz Sharif's meeting in Ufa in 2015 on the sidelines of Shanghai Cooperation Organisation mentioned terrorism and the need to expedite the Mumbai trial but Kashmir was conspicuously missing in it.
Leaders and media in Pakistan had criticised the Nawaz Sharif government over the absence of any mention of the vexed Kashmir issue in the joint statement.
Mr Basit said Mr Chaudhry's "heart was not in the right place" and argued that it was in Pakistan's interests that he should be immediately removed from his post as ambassador to the US.
He further said that if Mr Chaudhry was not removed then he should not be at least given any extension beyond February 27, 2018, the date of his retirement.
"May Allah help Pakistan when people like you with weak and dubious credentials are at such important positions," Mr Basit ended the letter with these grim words.
Mr Basit opted for an early retirement earlier this month and was replaced by Sohail Mahmood as the high commissioner.
It is pertinent to mention that Mr Chaudhry was appointed as the foreign secretary by ignoring Mr Basit.
Mr Basit was again ignored this year when his junior Tehmina Janjua was appointed foreign secretary, replacing Mr Chaudhry who was sent to the US as Pakistan's ambassador.
(This story has not been edited by NDTV staff and is auto-generated from a syndicated feed.)