Mr Pornpetch said the NLA is preparing to call a meeting for tomorrow because he expects a royal command appointing the NLA president and two deputies to be issued today.
Discussion of the proposed 2015 fiscal budget could be held tomorrow if the president and deputies receive royal endorsement; otherwise it will be postponed until next week, he said.
Surachai Liangboonlertchai, the NLA vice-president-designate, said the assembly would likely nominate a prime minister by the last week of this month at the latest.
It has been widely speculated that National Council for Peace and Order (NCPO) chief Gen Prayuth Chan-ocha will be nominated to become prime minister.
Mr Surachai said an NLA panel will draft guidelines governing NLA meetings. These could also address the assembly's selection of the prime minister.
"The NLA is empowered to select the prime minister by the interim charter. This is different from the NLA established after the 2006 coup. Back then, the coup makers appointed the prime minister," he said.
According to Mr Surachai, an interim government should be sworn in by the time the next fiscal year commences on Oct 1. Mr Surachai backed calls for NLA members to declare assets, saying former MPs and senators were obliged to do so.
However, enforcement rests with the National Anti-Corruption Commission, he said. He also noted that standing committees should be set up to scrutinise the work of the government and state agencies, but the number of these panels should be kept to a minimum to save budget funds.
Mr Pornpetch yesterday submitted his resignation as ombudsman, effective Sept 1, to avoid any conflicts of interest given his new role as NLA president.
Meanwhile, Puchong Nutrawong, the secretary-general of the Election Commission (EC), said yesterday that applications for membership of the National Reform Council (NRC) can be submitted from today until Sept 2. He said the EC, which serves as the secretariat for the committee tasked with selecting NRC members, expects to receive more than 3,000 candidates who will be shortlisted by administrative committees.
The NCPO will then choose 250 members from candidate lists submitted by administrative panels.
The NCPO yesterday appointed 11 seven-person screening committees to select NRC members who will oversee national reforms in 11 areas.
Committee members include NCPO legal adviser Visanu Krue-ngam for state administration, NCPO advisory chief Gen Prawit Wongsuwon for political reform, Mr Pornpetch for law and justice selection panel, former army chief Anupong Paojinda for local administration, former science and technology minister Yongyut Yutthawong for education and NCPO adviser for the economy Narongchai Akrasenee.
Others include NCPO advisor and former finance minister MR Pridiyathorn Devakula for energy, NCPO deputy chief ACM Itthiporn Supawong for public health and environment, NLA member Gen Noppadol Inthapanya for the media, NCPO adviser and former commerce minister Somkid Jatusripitak for social reform, and former deputy army chief Gen Dapong Rattanasuwan for other issues.
Altogether 173 NRC members will be picked by the 11 panels. They will work with 77 members chosen by provincial selection panels from each province.