Pep Guardiola

The FA said in a statement the yellow ribbon worn by the former Barcelona boss on his jacket in support of imprisoned Catalan politicians was in breach of its kit and advertising regulations.

Guardiola, whose side face Arsenal in the Carabao Cup final on Sunday, live on Sky Sports, has until 6pm on Monday, March 5 to respond to the charge.

City have lacked consistency since opening the season with 10 successive wins, and Guardiola conceded defeat in the title race after last weekend's 4-0 loss at Everton left them 10 points behind Premier League leaders Chelsea.

Their form has raised questions over the quality of Guardiola's squad and whether he believes he has the right players.

He said: "They are good players. I have respect for the guys, so why would I say the guys are not good?

The visitors led 3-0 at half-time thanks to strikes by Yaya Toure, via the penalty spot, a Havard Nordtveit own goal and David Silva.

However, things got even worse for the Hammers in the second half as further efforts from Sergio Aguero - his 18th goal in all competitions this season - and John Stones rounded off the scoring for City.

As a result, it will be City's name in the hat for the fourth-round draw on Monday, while Slaven Bilic and Co can now concentrate on trying to rise up the Premier League table.

De Bruyne opened the scoring with a clever free-kick as Guardiola's men maintained their perfect start to the Premier League season at the Etihad Stadium.

Guardiola has worked with a number of high-profile stars throughout his career such as Arjen Robben, Andres Iniesta and Xavi.

And the Spaniard has named Barcelona superstar Lionel Messi as the best player he has ever worked with, but says De Bruyne is right behind him.