After replacing Sandro Rosell at Barcelona, the new president insisted he will continue to defend the club over the Brazilian's controversial transfer from Santos
Rosell's resignation was confirmed at a press conference on Thursday evening, with former vice-president Bartomeu confirmed as the new chief at Camp Nou until the end of the current term in 2016.
"We are going to be very strict in the defence of our club against all the judicial and sporting authorities," the new president told reporters.
As he officially resigned as president, Rosell again insisted he had committed no wrongdoing regarding the Neymar transfer and said he was leaving the role due to unfair criticism and pressure being brought against his family.
Bartomeu added: "It has been an honour working with Sandro Rosell all of these years and I would like to give thanks to my fellow colleagues on the board for allowing me to lead this project.
"The first message as president of Barca is to announce that this project will continue until 2016. We feel strong and we will stay true to the values that have guided us through these years.”
On taking over the running of the club, Bartomeu stressed his aim was to ensure continuity in objectives and pointed to the upcoming referendum over the club's development of Camp Nou as a crucial area of focus in the coming months.
The new president continued: "I want to encourage the socios to continue supporting us in future. All of our challenges are as valid as ever.
"The future of the Camp Nou remains a priority - and we are playing for our future over the next few months.
"This is the best time in the club's history."
Bartomeu added that senior board members would have a further meeting on Friday ahead of another press briefing later that day in a bid to deal with the issues currently facing Barcelona.