Fernando Alonso has urged his Ferrari team to step up their efforts if he is to be crowned world champion this season.

Despite leading the title race for most of the year, the Spaniard has failed to win any of his last four races in including Saturday's Singapore Grand Prix.

Despite his nearest title challenger Lewis Hamilton being forced to retire last time out, Alonso is adamant that his team need to up their game.

"In the end it went well but we definitely can't go on like this," Alonso said.

"It can't always be the case that my closest rival retires, as has happened in the last two races, and we can't think of carrying on to the end of the season with qualifying sessions like [Saturday] when our performance was almost a second off the best."

Alonso currently boasts a 29-point lead in the championship standings.