Theo Walcott has finally signed a new contract at Arsenal, which has made him the club's highest-paid player on £100,000 a week. The England forward has committed for three and a half years and he has received a £3m bonus for remaining loyal.

The saga ended on Friday morning, bringing a tonic to player and club. Walcott, whose previous deal – worth £55,000 a week – was set to expire in the summer, had sought fresh terms to reflect his value on the pitch and in marketing terms. He is hugely popular in east Asia, where Arsenal are seeking to make commercial inroads, and his new salary contains image rights clauses.

"I am very happy to have signed a new contract here at Arsenal," Walcott told the club's website. "Thanks to everyone for their continued support, especially the manager, everyone at the club and most importantly the fans. I have made it clear from the start that I wanted to stay at Arsenal so I am pleased we have agreed a deal that everyone is happy with. What's important now is for the team to realise its potential and win trophies."

Arsène Wenger had spoken of his optimism on Thursday that the deal was close and the Arsenal manager has indicated that he could now look to pursue a new signing in the January transfer market. He has money to spend, although he has sounded a note of caution about the difficulties of buying players in mid-season.

The road to the Walcott agreement has been rocky, with the 23-year-old enduring frustration when he rejected the club's offer of a little under £80,000 a week in late August and found himself out of Wenger's starting lineup for more than two months. Walcott would have signed for £90,000 a week in August but his return to the team and his impressive statistics have allowed him to successfully push for more money. He has scored 14 goals in all competitions, his highest haul in a season.

Walcott, who joined Arsenal from Southampton in January 2006, has also seemingly wrung footballing concessions out of Wenger. He has never made any secret of his desire to play as the central striker and Wenger has granted him his wish in recent weeks, beginning at Reading in the 5-2 win on 17 December. Walcott hopes to lead the line at Chelsea on Sunday and he is determined to make an impact after misfiring for the past four matches.

He follows a quintet of young British players – Jack Wilshere, Alex Oxlade-Chamberlain, Kieran Gibbs, Aaron Ramsey and Carl Jenkinson – in signing a long-term contract extension at the club.