Changes to F1's Sporting Rules announced by the FIA's World Motor Sport Council today have cleared the way for Ferrari to supply Toro Ross with engines again next season.

The Italian manufacturer provided its Faenza rivals with engines between 2007 and 2013, after which, like its sister team, Red Bull, it switched to Renault for the new hybrid formula introduced in 2014.

Unhappy with the Renault engine, again like its sister team, Toro Rosso sought an alternative supply, and with Mercedes out of the question, Ferrari seemed the only realistic option.

However, as was the case with Red Bull, Ferrari was unwilling to supply the current spec units and the rules prevent manufacturers from supplying more than one specification of power unit... until today.

Following its meeting in Paris, the WMSC announced: "Power Units homologated in previous seasons may now be re-homologated. Previously no manufacturer could supply more than one specification of PU.

"The World Motor Sport Council was also advised that the FIA had agreed for Ferrari to supply a fourth customer team with a 2015-specification Power Unit in 2016."

Whilst Red Bull has yet to confirm the identity of its engine supplier, it is widely assumed that the Austrian team will remain with Renault for one more season before finding an alternative partner in 2017.