Culture Secretary Nicky Morgan said she had been prepared to “put aside differences” with Boris Johnson to take a job in his Cabinet.
Baroness Morgan had initially ruled out serving in a Government led by Mr Johnson in the run-up to his election as leader, but later relented to take on the job as head of the Department for Digital, Culture, Media and Sport (DCMS).
The former education secretary stood down as an MP at the election, but was appointed a peer in order to continue her Cabinet role.
She was sworn in as a member of the House of Lords on Monday after taking an oath.
Defending her decision to take a seat at the Downing Street table, Ms Morgan told The House magazine that the public expected “politicians to be able to put aside their differences and get things done”.
“My view is that I took the role in Cabinet when the Prime Minister offered it on the basis that I think it’s really important to have a variety of voices around the table with different views on the Conservative Party, different views on Brexit, and the Prime Minister understands and respects that,” she said.
“I also think that if you’re asked to serve your country and Parliament then you should say yes, unless there’s a very good reason to say no.
“The lesson from the last three-and-a-half years, and from the general election, is the country expects its politicians to be able to put aside their differences and get things done on their behalf. I hope that I’ve been able to show that this is possible.”
She deflected a question on whether she was simply “keeping the seat warm” for her successor at the department, with Mr Johnson reportedly planning a Cabinet reshuffle once Brexit is delivered on January 31.
“I’m not sure that the department would think that it’s a holding pattern,” the former Loughborough MP replied.
“The expectation is that he will want to have a refresh of his team in February – that’s obviously a matter for the Prime Minister.”
During the interview, the senior Conservative was critical of the Academy Awards judges’ decision not to nominate a single female in the category of Best Director.
Highlighting that it was not the first time the Oscars had been embroiled in controversy over its lack of diversity – it previously failed to nominate a single ethnic minority person in 2016 – she urged the judges: “They need to be specifically saying, ‘We want there to be more women’.”
On sport, she told Parliament’s magazine that betting “might well be” too intertwined with football.
Her comments come after fans wanting to watch certain third round FA Cup ties had to set-up a Bet365 account and deposit money to view the games.
The deal is being investigated by the Gambling Commission.
Ms Morgan said football needed to be more aware of its influence on society and the way it is “copied by others”.
She said: “Football is an enormously influential activity. I’m afraid it’s not just about money. It’s got to be about behaviours and the signals that you’re sending out.”