A319 First Officer reported receiving an ECAM for ENG 1 Thrust Reverser Fault shortly after takeoff around 1;000 ft. The Captain set the affected engine to idle and the crew requested vectors for an immediate return to the departure airport.

Narrative

After initial push we experienced our number two engine having trouble starting due to the cold weather. We returned the gate. After maintenance checked out the engine and got the ice cleared from the engine we were able to push a second time and got a good start on both engines. We then proceeded to be deiced; and took runway XX in ZZZ. After rotation around 1;000-1;500 ft. we had an ECAM Message reading ENG 1 Thrust Reverser Fault with an amber LAND ASAP. There were zero other messages or steps to take. The Captain expressed he has experience in this situation and pulled number 1 engine to idle. I then activated autopilot. The captain then ran checklists and advised ATC. We were given vectors to return to runway XX at ZZZ. The Captain then called the Flight Attendants and gave them the required information for the situation. On downwind the Captain took flight controls and transferred ATC to me. In this high workload situation we briefly considered contacting operations but decided to wait till we were on the ground. After landing and stopped I found nothing in the QRH. The manual confirmed the ECAM messages were correct and only gave one step to take which was to pull the affected engine to idle. Which is what we did. The Captain performed his duties perfectly and in the event of an actual thrust reverser deployment at that phase of flight the actions of the Captain could have saved our lives.