New Delhi: It will be another birthday abroad for Prime Minister Manmohan Singh on Monday when he turns 79, the fourth time in the past eight years after he assumed office.

A workaholic who shies away from any celebrations, Singh celebrates his birthday on September 26 as his parents had given it as his date of birth to get him admitted in a school in a village now in Pakistan during the pre-partition days.

However, his actual date of birth remains a mystery.

Singh, who is now abroad on a six-day visit to the United States, will transit from New York to India via Frankfurt during his birthday.

On previous such occasions, his birthday was celebrated on Air India One.

In his first year as Prime Minister in 2004, he celebrated his birthday mid-air on way to Geneva from New York on Air India's Boeing 747-400.

Singh then did not cut the two-and-a-half kg fruit cake specially made for the occasion but joined everyone in having a slice of it.
He had then told accompanying reporters "I really don't know my birthday. This is the date mentioned in my school records."

Once again, four years later, he celebrated his birthday in Washington and the next year he turned another leaf in his life on air while returning from G-20 Summit in Pittsburgh in the US and heading to Geneva.

Singh was born to Sardar Gurmukh Singh and Amrit Kaur in 1932 in Gah of Punjab, which is now in Chakwal District of Pakistan.

Manmohan Singh is the 13 th Prime Minister of India and is the only PM after Jawaharlal Nehru to come back to power after completing full five-year term.

Born on September 26, 1932, Singh is also the seventh PM from the Indian National Congress.

He has carried out economic reforms in India in 1991, during his tenure as the Finance Minister, under the leadership of PV Narasimha Rao, from 1991 to 1996. These reforms resulted in the end of the Licence Raj system, helping to open the Indian economy to greater international trade and investment.

Singh is number 18 on the 2010 Forbes list of the world's most powerful people and the magazine described him as being "universally praised as India's best prime minister since Nehru".

Pranab greets Manmohan

Manmohan Singh received birthday greetings from his senior-most cabinet colleague Pranab Mukherjee a day in advance.

Mukherjee, who flew here from Washington to have urgent consultations with the Prime Minister to brief him on discussions with Fund-Bank leaders and US investors, greeted Singh.

"I wished him on his birthday. Normally I am not good at these dates and I miss. But helpfully my staff told me about it so I took a bouquet of flowers and gave it to him," he said.