THERESA MAY has been branded “embarrassing” on defence and the Armed Forces in a brutal attack by one of her own MPs.

The Sun can reveal former squaddie Johnny Mercer ripped into the PM’s chief of staff in the Commons – claiming the Government was refusing to back the military.

2 Tory MP Johnny Mercer spoke out against the Prime Minister's record on defence

Sources claimed he hit back at Gavin Barwell after being challenged why he was so critical of the Government’s record. And the MP told the aide he had “given up” on Downing Street.

The shouting match is thought to have occurred after Prime Minister’s Questions last Wednesday.

A source said: “Johnny lost it. Gavin asked what he was playing at.

“Johnny gave it to him with both barrels, jabbing his finger and saying how the PM and No.10 were embarrassing him and he could no longer defend his own Government when he speaks to people in the military.”

2 Theresa May has been criticised for failing to back the military Credit: EPA

Mr Mercer – MP for Plymouth Moor – served as a captain with 29 Commando Regiment Royal Artillery in Afghanistan.

Last week he accused the PM of “not getting it” over the Government’s refusal to offer Army veterans facing prosecution for killings in Northern Ireland an amnesty.

Mr Barwell is believed to have challenged the MP over the comments.

MPs are also furious at Theresa May’s repeated failure to commit to the UK remaining a “tier one” military power.

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In June, the PM sparked suggestions of spending cuts by only saying she was committed to Britain remaining a “leading military power”.

Tory backbenchers are also livid with the appointment of Stuart Andrew as ministerial aide at the Ministry of Defence two months ago. One told The Sun: “He has no experience whatsoever. But he’s been put in charge of equipment and defence exports.”

Mr Mercer declined to comment last night.

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