Romain Grosjean has made it clear he remains firmly against the decision to introduce the Halo cockpit device in 2018, doubting it is totally ready for Formula 1.

The controversial announcement was made as motorsports governing body, the FIA overruled a nine-to-one vote by teams against the Halo at a meeting of the Strategy Group last week, using safety grounds as the reason for its implementation.

The decision has caused outrage among fans and is likely to be a major topic at this weekend's Hungarian Grand Prix, with the Frenchman, who was made a director of the GPDA (Grand Prix Drivers Association) earlier this year, the first man to comment.

"Personally, I think it was a sad day for Formula 1 when it was announced," the Haas driver claimed. "I am still against it, I don't think it's got a [place] in Formula 1."

Giving his reasons for his position, Grosjean doubts enough testing for ever scenario has yet to be completed despite the multiple Practice 1 outings towards the end of last season.

"As a GPDA member and director, and a driver, I need to thank the FIA for all the research, because the research has been pretty strong, and the Halo is a strong device against a lot of cases," he acknowledged.

"But there are occasions where it can get worse, which I'm not particularly a fan of, and there are a few problems that we may have that we haven't thought of.

"Seeing the starting lights on the grid... no one has tried that, and they're always different. Seeing flags on the side... things like that, we need to see a bit more of it."

The 31-year-old also clarified the position of the GPDA, after a statement realised the day after welcomed the FIA's decision despite the known opposition from many drivers.

"Again, the GPDA is not here to tell the FIA what to do and what not to do on safety, we backed off from the discussion a long time ago and issued a statement saying, 'thank you for the research, thank you for taking the safety up in Formula 1'," he explained.

"We [as the GPDA] are not supporting particularly the Halo, we are just supporting the fact that the FIA is trying to make the car safer.

"I don't want to stop the safety research because I think it's great, and since 1995 evolution has been crazy-good, but hopefully we'll get better solutions to what we have now."

Grosjean also admits some of his own dislike for the Halo comes from a very negative first experience with it last year.

"I guess you get used to everything in life, but hopefully I don't get as bad as I was in Brazil because it got me pretty sick," he revealed.

"You are trying to focus with something in front of you all the time, in the middle... I don't know, my eyes kept coming together, it was a bit strange."