Mercedes say they will have to consider dropping Lewis Hamilton or Nico Rosberg if the pair cannot race together cleanly.

The ultimatum from Mercedes sports boss Toto Wolff comes in the aftermath of the drivers' collision in Belgium.

The team have made it clear before this weekend's Italian Grand Prix that there must be no more on-track contact.

"We would have to take decisions and take the consequences of having a different line-up," said Wolff.

"If we are not able to manage the two of them following the Mercedes-Benz spirit then we need to admit that," added Wolff.

Mercedes have taken disciplinary action against Rosberg for the collision at Spa on 24 August, for which the German has taken responsibility and apologised.

The collision caused a puncture in Hamilton's car and forced him to retire, and Rosberg subsequently opened up a 29-point advantage over his team-mate in the championship.

Wolff, speaking in an exclusive interview with BBC Radio 5 live, refused to give details of the internal action taken against Rosberg.

Wolff said: "When you are managing a team it is very important to keep it balanced. I would very much like the penalties we have been implementing to stay within the team because it is just not fair on the driver to discuss that in public.

"We have made it very clear this is an unacceptable scenario for us, for both of them. We don't want this to happen ever again."

Meanwhile, Hamilton has queried the FIA's decision not to investigate the collision with Rosberg.

The governing body decided not to look at the incident again despite it emerging after the race that Rosberg had told his team he had known the two could crash.

Hamilton said: "Can we race a lot closer and if the other guy is out of the race nothing will happen? Or if it happens again will there be a penalty?

"We are always asking to be able to race. But there is a fine line."

FIA stewards looked at the clash while the race was in progress and decided it was a 'racing incident' that required no further action.

The governing body has said there was no reason to revise that view.

The German, of whom team bosses were highly critical, said: "I was not proud of the way it went in Spa, because in general I really want to contribute to my 'sport'. I want it to be the most entertaining sport in the world and if I am able to contribute I am very happy about that and I'm sure we have."

He described his relationship with Hamilton, and between the two sides of the Mercedes garage, as "a healthy rivalry".

Hamilton, asked whether he could trust Rosberg for the rest of the season, said: "Trust is a big word and it is not something I would apply to a race on the track. Nico and I have been racing for a long time, we set a good foundation a long time ago and that's what we work from."

Hamilton said the decision had made no difference to his desire to stay with Mercedes beyond his current contract, which ends in 2015.

"I am constantly talking to the team and the priority is to win the championship," he said. "I have a contract for another year so there is no rush, but I would like to say I see my future with Mercedes."

Kevin Magnussen's aggressive driving has been backed by Formula 1 rival Red Bull, who think it was harsh of the stewards to impose a penalty on the Dane at the Italian Grand Prix.

The McLaren driver was given a five-second stop/go sanction for having forced Valtteri Bottas off the track at Monza's first chicane in a fight for position.

The stewards' decision left both Magnussen and McLaren frustrated, especially coming after Nico Rosberg escaped any sanction for colliding with Lewis Hamilton at the Belgian GP.

Red Bull boss Christian Horner said he believed that the Magnussen/Bottas incident was nothing out of the ordinary considering they were battling hard with each other.

"I think he was penalised for not giving him space and I think that it's a different incident [to] the one that happened in Spa," explained Horner.

"But personally, I thought it was a racing incident at Turn 1. He had the inside line [and] that's his prerogative if he keeps going there.
"It's not 'after you sir' - it's racing, it's wheel-to-wheel combat.

"I thought the move he made into Turn 1 was a legitimate move, but the stewards thought otherwise."

F1's governing body has reportedly banned certain radio communications between engineers and drivers with immediate effect.

Germany's Auto Motor und Sport reports that the increasing trend for radio instructions about how the drivers should actually drive the cars have proved a major turn-off for the fans.

One example crackled over the TV-transmitted radio on Friday at Monza, when championship leader Nico Rosberg told his Mercedes engineer Tony Ross: "Give me driving instructions."

And Ferrari's Andrea Stella told Fernando Alonso, regarded as perhaps the very best F1 driver, to "take another line in turn 10" of the fabled Italian circuit last weekend.

According to Auto Motor und Sport on Tuesday, the FIA is now banning these types of radio messages to drivers, effective as of next weekend's Singapore round.

It is also believed the FIA wants to clamp down on instructions to drivers including which dials and buttons they should press on the steering wheel.

The report said the Paris federation is enforcing the 'ban' simply by invoking a clarification of the existing Article 20.1 of the sporting regulations, which states: "The driver must drive the car alone and unaided."

Sebastian Vettel has advised us that he will be leaving Infiniti Red Bull Racing at the end of the 2014 season.

We want to warmly thank Sebastian for the incredible role he has played at Infiniti Red Bull Racing for the last six years.

Since joining the team in 2009, Sebastian, together with Infiniti Red Bull Racing, has scored 38 wins, 44 poles and eight World Championships, including four Drivers' titles and four Constructors'. If you include Sebastian's success at Red Bull's second team, Scuderia Toro Rosso, the Red Bull total increases to 39 wins and 45 poles.

As we wish Sebastian well in the next stage of his career, we also look to the future with excitement, as the vacancy makes way for the next generation of Red Bull racers.

The Red Bull Junior Programme has developed some proven talents in recent times, including Sebastian Vettel and Daniel Ricciardo, who has excelled in the RB10 and become a three-time Formula One race winner in his first season with the team.

We're pleased to announce that Daniel will be joined in the team for 2015 by another rising star from the Junior Programme, Daniil Kvyat.

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