Mercedes Formula 1 boss Toto Wolff has suggested rules surrounding the blue flags shown to backmarkers during a grand prix be reviewed.

His comments come in the wake of the Singapore Grand Prix which saw Lewis Hamilton held up by Romain Grosjean as he battled with Sergey Sirotkin.

The delay saw Hamilton’s advantage over second-placed Max Verstappen evaporate, and provided the Red Bull driver an opportunity to make a move for the lead.

Mercedes’ second driver, Valtteri Bottas, also had struggles with traffic after finding himself behind Nico Hulkenberg but without the pace advantage to close within the prescribed distance for the Renault to be shown blue flags.

The two incidents left Wolff suggesting drivers need greater awareness when the leaders were approaching them, and that regulations dictating when blue flags are shown be adjusted at street circuits.

“The first moment obviously you’re angry that you have lost the gap,” Wolff said of Hamilton’s delay behind Grosjean.

“But you need to accept that these guys are fighting for position and trying to have their own best race. And we have to respect it.

“I think the drivers need to discuss this among themselves, that if the leaders come, and it’s close, that maybe they should have more of a global perspective what’s happening behind them.

“I think that in a racing car sometimes you don’t know what’s happening and just see that the leader is coming and you’re fighting for your own position. You have to respect everybody’s struggle to perform.”

Of Bottas’ trouble in traffic, Wolff suggests the gap between a backmarker and leader be increased at circuits where overtaking is difficult.

Currently blue flags are only shown when a front runner is within 1.2 seconds of a lapped car, a buffer Bottas wasn’t able to close on the Renault.

It left the Mercedes driver potentially vulnerable to fifth placed Kimi Raikkonen, while Daniel Ricciardo chased them both down with fresher tyres.

“He was upset because he couldn’t close up to Hulkenberg, which was a shame,” Wolff explains of Bottas’ predicament.

“Kimi struggled less so, but when you look at Daniel, who was on a fresher tyre, on an ultra(soft), probably raw pace two seconds quicker than Kimi, he couldn’t overtake Kimi either.

“So again I think something which we need to look at, whether the gap, the 1.2 seconds, is a gap that needs to be adjusted for street circuits.

“It’s a rule and we have to respect the rule, and if we can optimise it for the future we have to look at it.”

At the flag, Bottas maintained fourth while Hamilton extended his lead over Verstappen to win once the pair had cleared the Grosjean/Sirotkin battle.

Hamilton now holds a 40 point advantage in the drivers’ championship standings over Vettel, while Mercedes holds a 37 point advantage at the top of the constructors’ standings.