movement was now mature enough for a directly-elected political leader.
"If we have to remain in exile for several more decades, a time will inevitably come when I will no longer be able to provide leadership," he said in the letter read by the speaker.
"Therefore, it is necessary that we establish a sound system of governance while I remain able and healthy, in order that the exiled Tibetan administration can become self-reliant rather than being dependent on the Dalai Lama," he said.
The matter is scheduled to be debated on Tuesday, with the Dalai Lama requesting an amendment to the exiled government's constitution allowing him to step down.
The Dalai Lama's political title is largely symbolic and he will retain the more significant role of Tibet's spiritual leader.
Announcing his desire to step down last week, he made clear that he would not be withdrawing from public life and remained "committed to playing my part in the just cause of Tibet".
It is not the first time the Dalai Lama has asked to be released from his ceremonial political responsibilities, and the parliament has rejected similar requests in the past, arguing that there was no replacement of equal stature.
Observers say the Dalai Lama is more adamant this time, and expect that his temporal duties will be assumed by the exiled government's new prime minister, who will be elected in a final round of voting on Sunday.
"If we are able to implement such a system from this time onwards, I will still be able to help resolve problems if called upon to do so," the Dalai Lama said.
"But, if the implementation of such a system is delayed and a day comes when my leadership is suddenly unavailable, the consequent uncertainty might present an overwhelming challenge," he added.
There are three contenders for the post of prime minister, with Lobsang Sangay -- currently a visiting research fellow at Harvard Law School -- seen as the front runner.
The other candidates are Tenzin Tethong, a former representative of the Dalai Lama in New York and Washington, and Tashi Wangdi, who has run half a dozen departments of the government-in-exile over the years.
In a debate hosted on Sunday by US-based broadcaster Radio Free Asia, all three candidates voiced clear reservations about assuming the Dalai Lama's political title and urged him to reconsider stepping down.
"The Dalai Lama's decision to transfer authority to an elected Tibetan leadership naturally comes to me as a serious concern," said Lobsang Sangay.
"I support 100 percent that a collective appeal must be made to ask His Holiness to continue to hold leadership of the Tibetan people," he added.
Tethong said the Dalai Lama's leadership in all spheres was critical.
"I'm of the view that Tibetans must strongly urge him to continue to lead the Tibetan people as a whole," he said.
China, which brands the Dalai Lama a "splittist" bent on Tibetan independence, has accused him of playing political "tricks" to deceive the international community.
Analysts say relinquishing his political title would be largely symbolic, with the Dalai Lama remaining the global figurehead of the Tibetan movement and key arbiter on important policy.
The Dalai Lama fled his homeland in 1959 after an unsuccessful uprising against Chinese rule, and established his exiled government in the northern Indian hill town of Dharamshala.