Mercedes chief and Lewis Hamilton reveal one of the key catalysts for their strong 2017 campaign

Lewis Hamilton has credited his off-season meeting with Mercedes F1 boss Toto Wolff as one of the catalysts for his improved form in 2017.

The Briton has been almost flawless this season when the Mercedes package is at its best and only struggled when the car was not at its best at certain tracks, namely Monaco, Singapore and Hungary.

Hamilton was trailing Sebastian Vettel in the championship in the first-half of the season, but since he took the lead at the Italian Grand Prix, he has been untouchable. He benefitted from some misfortune suffered by Ferrari but he made his advantage count and is on the cusp of a fourth drivers' title after winning five of the last six races.

It was not the same last season as his battles with then teammate and 2016 Formula 1 world champion Nico Rosberg caused tension within the team. Things boiled over in the final race of the season in Abu Dhabi when he disobeyed a direct order from the team's pit wall, which incensed the Mercedes bosses.

Hamilton, who was leading in the final race, slowed down the pace during the race in order to push his teammate back into the chasing pack in a final attempt to win the title. However, Mercedes did not approve of his tactics and asked him to increase his pace – a call which he ignored.

Wolff was critical of his actions and threatened a penalty for his driver, but softened his stance later following Rosberg's shock decision to retire from the sport.

Mercedes and Hamilton were not on good terms after the end of the season, and now admitted that the private meeting at the end of last year in the Mercedes chief's kitchen was crucial in helping them address the problems and start afresh in 2017.

"Going to see Toto at the end of last year was crucial in terms of solidifying longevity within the team," Hamilton said after securing his ninth win of the season at the US Grand Prix, as quoted on Sky Sports.

"To just put everything on the table and say what's needed to say. Then to build on creating a new stronger relationship, which we've done," the Briton explained.

"We had a difficult moment in Abu Dhabi last year and we came back together a couple of days later and had a long evening in my kitchen and put it all out," Wolff said, agreeing with his drivers' comments.

Wolff believes Hamilton came into 2017 with a completely different mindset and recently admitted that he had gone up a level since they started working together five years back. He also believes his more harmonious relationship with new teammate Valtteri Bottas has also played a part in the team being stronger, especially as they had to weather the storm from Ferrari, who pushed them at least in the first half of the season.

"Maybe all the frustrations and the questions that had grown over the years were all dismantled. We went off and he came back with a great mindset. He has grown stronger through the year.

"You can see also the relationship with Valtteri is an important factor. The spirit is great within the team, and through all the difficult moments, that was an essential piece of the jigsaw," the Mercedes boss added.