Labour MP Chris Bryant has taken offence after Culture Secretary Maria Miller said marriage was the “gold standard” – with the MP claiming it devalued his own civil partnership.

Mrs Miller, who is also the Minister for Equalities, made the remarks on Tuesday in front of a committee of MPs that are studying the government’s Marriage (Same Sex Couples) Bill.

Giving evidence to the committee, Mrs Miller was asked by Mr Bryant why ministers were not also considering allowing heterosexual couples to enter into civil partnerships.

The senior Tory cabinet minister said: This bill is all about extending marriage – that is what we believe is the gold standard – that is what people aspire to.”

In response, Mr Bryant, who is also a shadow immigration minister, replied: “That makes my civil partnership not feel like the gold standard. She may want to rethink the way she talks about it.”

Mrs Miller said she had not meant to cause offence and was simply stating that “everybody should have the opportunity to access what is an internationally recognised status.”

Last Tuesday, MPs voted in favour of the bill by 400 to 175, a majority of 225.

However, David Cameron’s personal authority was left weakened. 136 Conservatives – almost half of the party’s MPs – opposed the bill.