New Delhi: A day after the government said that her tenure as Foreign Secretary has been "curtailed", Sujatha Singh on Thursday claimed that she had actually sought early retirement.

Singh, who was in effect sacked late last night seven months before her two years tenure was to end, has sent a farewell email to her colleagues in foreign service which makes no reference to the abrupt end to her service.

S Jaishankar, Ambassador to the US, was appointed as the new Foreign Secretary in a surprise decision by the Union Cabinet's Appointment Committee, which is headed by the Prime Minister. The sacking of Singh has come under criticism from Congress.

In her e-mail dated January 28, Singh said that she had sought early retirement from the government service after 38 years. She, in her farewell message, speaks glowingly about the foreign service.

"I believe that the Foreign Secretary, as Head of this Service and the senior-most civil servant in the Ministry, plays a critical role in being the main point of interface with the political leadership, in giving objective advice that takes into account India's foreign policy interests over all connected and interlinked aspects.

"While individuals can and do play a critical role in building institutions, I believe that no individual is larger than the institution. It can never be about individuals. It has to be about institutions and how institutions interface and coordinate with each other," Singh said in her e-mail.