Zaha Hadid Architects has been shortlisted to design a $1 billion (£650 million) new parliament building in Iraq.

A senior architect with the practice, Iraqi-born Mohamed Al-Jubori, was one of a number to attend a presentation at the Ishtar hotel — formerly the Sheraton — in Baghdad last month at which Iraqi parliament president Osama al-Nujaifi gave bidders a project briefing.

The practice already has one contract in the country of Hadid’s birth — a new headquarters for the Central Bank of Iraq which it won in 2010 — but the parliament building in the middle of the Iraqi capital promises to be a still more potent symbol of the new Iraq.

A spokesman for the firm confirmed it was chasing the job but declined to comment further.

Also in contention is another British practice, Assemblage, which has linked up with Buro Happold and Davis Langdon, owned by US giant Aecom, plus Iraqi firm Al-Khan and Canadian practice Adamson, currently working on the Shard in London, which would act as executive architect.

Assemblage director Peter Besley said: “It has to be an international landmark but it needs to be a deeply regional design so it has a number of roles to play.”

The full shortlist, selected by Iraq’s ministry of construction and housing, is a closely guarded secret but a third contender is Dewan Architects, which has offices in Baghdad as well as across the Middle East including Dubai and Saudi Arabia. A number of French and German infrastructure architects are also believed to be on the list.

The new complex will be built at the disused Al Muthana airport in the middle of the city. This was due to be the location of a super mosque planned by Saddam Hussein. Construction was halted by the US-led invasion in 2003, but some structure exists, including a series of eight 45m-high reinforced concrete columns.

Besley said firms had been told they could either keep the columns or knock them down, adding: “It will be an important aspect as to how those columns are treated.”

Entrants have until the first week of July to return their proposals to a technical committee before an international jury is drafted in to make the final decision. A winner will be chosen towards the end of this year.

Besley added: “They have divided the judging panel from the organising committee to ensure the result is transparent.”

In addition to a new parliament building, the winning architects will also be asked to design accommodation for MPs as well as more government buildings along with a new hotel and public parks for the site which is next to the Tigris river. They will also have to produce a masterplan for the surrounding part of the city.

The new parliament is part of Iraq’s post-war rebuilding programme. Last summer its prime minister Nouri al-Maliki said it wanted to improve its roads, airports and seaports while the US government’s foreign aid agency, USAID, is producing a series of investor guides aimed at interesting developers in new hotels, housing and shopping malls.