Plans are at an early stage and the council is seeking interested firms to look at building options on the two major projects, both expected to cost around £60m to build.

The Welsh Government and Cardiff Council are exploring a number of funding options, including potentially borrowing – with a low interest long-term repayment term – from the Treasury’s Public Works Loan Board, as well as through the use of tax increment financing.

Talks with other cities and developers have seen it draw up plans for a 15,000-seat capacity indoor arena in a horse-shoe layout, rather than conventional fan-shaped floor plate.

This would be able to stage major sporting events and concerts, as well as annual party political conferences.

Alongside this the council also aims to deliver a 1,500-seat international conference centre with around 500,000 sq ft of exhibition space.

The plans are an essential part of the Labour council’s vision for boosting the capital’s economy over the next 20 to 30 years.

Interested contractors should submit their response to [email protected] or call 02920 873704.