The protest was the latest in an almost 10-month campaign rejecting military rule and a coup on October 25. The Khartoum resistance committees which organised the protests said they were building towards a general strike on Wednesday.
"We are challenging them, in order to achieve our demands," the committees said in a statement a day earlier, announcing their intention to march towards the airport instead of the typical march towards the presidential palace.
Teargas was deployed to stop thousands of protesters about 2 kilometres away from the airport, and a large number of soldiers were seen deployed in its perimeter.
The rest of the capital was clogged with traffic as the main artery was blocked.
Last year's coup ended a power-sharing arrangement between the military and a civilian coalition to oversee a transition towards democracy following the 2019 overthrow of long-time autocratic leader Omar al-Bashir.
But after months of protests, and talks facilitated by western diplomats, there has been no movement and the country is at a political and economic standstill.
"We will continue protesting until the coup is brought down, and we bring back civilian rule. We will not stop and we will not get tired," said Hassan Ali, a 38 year old protester.
(Reporting by Khalid Abdelaziz; Writing by Nafisa Eltahir; Editing by Josie Kao)
By Khalid Abdelaziz