Former Premier League referee David Elleray believes video assistant referees could be introduced to the elite game in time for next year's World Cup in Russia.

Now technical director for football's law-making body IFAB, Elleray told The Times newspaper live trials of the system have already ironed out problems and more countries have signed up take part in further testing.

T he results of those early trials, held mainly in Italy, the Netherlands and the United States, will be discussed at next month's IFAB annual general meeting in London, with major football nations such as France, Germany and Mexico already keen to look at the system themselves.

Elleray said: "We are very happy with the progress that has been made. We have gone from almost nothing to more than a dozen countries, and we have already found out what we can do better.

"One or two things did not go so well at first but it would be a great shame if people get the idea that it is not going to work. It has so far worked better than a lot of people have anticipated.

"If the trials go well, FIFA would like to have the option to use it for the World Cup next year. England are also following this closely and may well become part of it in the future."

VARs were used at a major competition for the first time in December's FIFA Club World Cup in Japan, with some criticism over how long it took to award a goal Cristiano Ronaldo scored for Real Madrid against Club America because of confusion between the officials on whether he was offside or not.

Elleray, however, told the newspaper this is why the system is being so rigorously tested and changes to the way the officials communicate with the VAR have already been made.

He added that more work is needed on educating officials on how to use the system but said "accuracy is more important than speed", so fans may have to get used to the idea of slight breaks in action while the correct decisions are reached.