Welsh Labour MP Steve Witherden has apologised after being reproached for drinking milk from a carton in the House of Commons last week.
Mr Witherden, who was newly elected for Montgomeryshire and Glyndwr in July, was gently reminded of the strict no food or drink rules when in the Chamber.
In a statement, a spokesperson said Mr Witherden was “still learning the rules of the Chamber” but he would “not be ashamed of supporting British dairy farmers”.
It follows several reports of MP blunders in Westminster, as the 335 newly elected MPs get to grips with the historic rules of the Chamber.
All Welsh Conservative MPs lost their seats in July, while 13 new MPs representing Labour, Plaid Cymru and the Lib Dems took their places.
It has been confirmed refresher sessions on conduct are being carried out for new MPs but that they are typically held on a “rolling basis” to keep members of parliament in check.
There are long-standing conventions for debate in the Chamber, such as MPs only being able to take part with the speaker or deputy speaker’s permission and the occasional need for time limits on speeches, as well as stressing that the order in which speakers are chosen is at the speaker’s discretion.
New MPs have stressed their frustration with some historical traditions in the past, such as “bobbing,” whereby they must briefly and repeatedly rise in their seats in order to catch the Commons speaker’s eye to be called to speak.
In a statement, a spokesperson for Mr Witherden said: “Whilst I am sure like many new MPs he is still learning the rules and won’t be planning on doing it again, he would certainly not be ashamed of supporting British dairy farmers considering how badly they were let down by the last government.
They added: “Milk is an excellent source of protein and calcium and can be a nutritious part of a balanced diet.”
Both the Senedd and the Chamber prohibit any food or drink other than water and unless needed for health reasons, which will need to be cleared prior to meetings.