Elon Musk aims to send the first humans to Mars by the year 2028 to settle the Red Planet. But where some space experts believe Mars will not be colonised before the end of the century, the SpaceX CEO has much bolder plans. In March this year, the South African billionaire told his 27.8 million Twitter followers a “self-sustaining city” on Mars could be built by 2050. Now, in a series of tweets, Mr Musk told his followers how much that city would cost.

On Saturday, August 10, the SpaceX boss was asked to estimate the total cost of a self-sustaining civilisation on Mars. According to Mr Musk, the figure rests somewhere in the ballpark of about £82.8billion to £8.28trillion. Mr Musk tweeted: “Between $100B and $10T.” Justifying the exorbitant price tag, Mr Musk said £82.8billion ($100billion) would be the absolute minimum, considering the cost of shipping payloads to Mars. READ MORE: Elon Musk teases 'great progress' in 'race to Moon and Mars'

SpaceX news: Elon Musk placed a price tag on building a civilisation on Mars

SpaceX news: The company's proposed development of a city on Mars

When discussing his plans in March, the SpaceX boss estimated the goal could be achieved if started in five years.

Between $100B and $10T Elon Musk, SpaceX CEO

The plan also involved 10 orbital synchronisations and factored in millions of pounds of cargo being shipped to Mars. Mr Musk tweeted on Monday: “Approx min payload to Mars to nearest order of magnitude, so at $100k/ton, cost would be $100B.” Mr Musk then teased the possibility of a Mars-wide internet network by building a Starlink constellation above the Red Planet. Starlink is a network of low-Earth orbit (satellites) being developed by SpaceX to cover the entire planet with broadband coverage. READ MORE: How does the Starship compare to NASA powerful Saturn V?

When asked by Twitter user Walter MacVane about connecting Earth’s and Mars' Starlink constellations, Mr Musk replied: “Will be needed for sure. Bandwidth, no problem, latency is a challenge.” Mr Musk has argued the case for space colonisation for many years now. In 2014, he said: “I think there is a strong humanitarian argument for making life multi-planetary in order to safeguard the existence of humanity in the event that something catastrophic were to happen.” But before SpaceX can make any claim to the Red Planet, the California-based rocket manufacturer first has to get there. The goal is to construct a powerful two-stage rocket system dubbed the Big Falcon Rocket or BFR for short. READ MORE: Inside SpaceX's Crew Dragon Spaceship REVEALED

SpaceX news: Elon Musk's cost estimate of building a civilisation on Mars

SpaceX news: The 2016 design of the Starship spacecraft