"The fulfilment of the constitutional demand of the people in the Darjeeling hills, which is deeply connected with the national identity of the Indian Gorkhas, will provide long-awaited justice to their patriotism, which has been second to none," Mr Chamling said in a letter written to Union Home Minister Rajnath Singh on Tuesday and made available to the media on Thursday.
"The creation of Gorkhaland will restore permanent peace and prosperity in the region. Sikkim will be hugely benefited as her developmental tempo can thus be maintained," the Chief Minister said.
Mr Chamling also highlighted the problems Sikkim faced due to recurring blockading of its lifeline National Highway-10 during the last 30 years of the Gorkhaland agitation.
"The blockade of transportation of essential goods and the unrest causes unmanageable inconvenience. Also, the atmosphere of uncertainty along NH-10 poses great threat to lives as well."
He recalled that the Sikkim assembly had passed a resolution in 2011 seeking "a permanent solution to the pressing and longstanding problem of the people of Darjeeling hills".
Meanwhile, West Bengal Education Minister Partha Chatterjee criticised Mr Chamling's stand, saying all state governments should function within their constitutional limits.
All major political parties in the hills, including the GJM, and West Bengal opposition parties -- the Left Front, Congress and BJP -- boycotted a state government-sponsored meeting on Thursday in Siliguri.
The Left Front accused the ruling Trinamool Congress of trivialising the "sensitive issue" of Gorkhaland. The Congress questioned the meeting's effectiveness in the absence of Chief Minister Mamata Banerjee.