Minister had also told them that India would tackle diplomatically the boundary issue with China.
The delegation met Singh to seek review of defence strategy for the eastern sector in view of Chinese incursions and expressed serious concern over reports of a dam being constructed by China on Brahmaputra river.
"The Prime Minister said no dam is being constructed and only run-off-the-river construction has been made," Khandu told reporters while citing a letter from Chinese government.
A media report last week had said that China was building a big dam on Brahmaputra river, prompting India to express concern over the development as it would change the course of the river and could result in submergence of low-lying areas downstream.
India has no problem with run-off-the-river constructions but building of a dam as it involves storage of water.
When the delegation raised the issue of Chinese incursions into the state, the Prime Minister assured them that the Centre will "tackle" the boundary question with the neighbouring country bilaterally.
"The Prime Minister told us not to worry. He said the Centre will tackle with the situation bilaterally," said Congress MP from Arunachal West Takam Sanjoy, who was part of the delegation.
Khandu said the state is an "integral part of India" and the recent election there is a reply to Chinese claim over the state.
Sanjoy said the delegation requested the Prime Minister to give a big push to infrastructure development to ensure better surveillance over Chinese activities.
The delegation also urged Singh to create a para-military force comprising youths from the state only.
"We demanded formation of Arunachal Scouts comprising only youths from the state as they are willing to join the forces to defend their territory," Sanjoy said.
China, which lays claim over Arunachal Pradesh, recently objected to the Prime Minister's visit to the state leading to a war of words between the two countries.
Besides responding strongly to the Chinese objection, India retaliated by questioning China's engagement in projects in Pakistan-occupied Kashmir (PoK) and asked it to stop such activities taking a "long-term view" of India-China relations.
The delegation, in its memorandum, also requested Singh to take all measures to ensure success of the upcoming visit of Tibetan spiritual leader Dalai Lama to the state next month.
China has objected to the proposed visit of the Dalai Lama.