Downing Street has been forced to clarify the defence secretary’s claim that the UK has previously fought “illegal wars”, in an apparent reference to Iraq.

Prime minister Boris Johnson’s official spokesperson said Ben Wallace was expressing a “personal view” when he accused Labour of presiding over “illegal wars” when in government.

The spokesperson added: “Neither the government nor the Chilcot inquiry has expressed a view as to whether the UK’s participation in the war was legal.”

It bore resemblance to when Nick Clegg was forced to clarify his claim that the Iraq war was illegal when he was deputy prime minister in 2010, amid fears it could aid charges against the government in international courts.

It is the second embarrassment for Wallace this month, having been forced to apologise for breaking social distancing rules by shaking a man’s hand on his way to a cabinet meeting.

He made his “illegal wars” comments during a heated Commons debate on laws to limit prosecutions against troops for actions taken in operations overseas. 

At one stage, Wallace told Labour shadow defence secretary John Healey: “Much of the mess we are having to come and clean up today is because of your illegal wars, your events in the past, and the way you have run the safety for our forces.” 

Healey hit back: “That is not worthy of the office of the secretary of state for defence”.

Tony Blair’s Labour government has long faced widespread criticism for pushing UK forces into wars into Iraq and Afghanistan.

In 2004, United Nations secretary general Kofi Annan said the US-led invasion of Iraq a year prior was “illegal” because it contravened the UN charter.

The Chilcot inquiry found in 2016 that the UK decided to take military action in Iraq before all other peaceful options had been carried out and undermined the UN Security Council in the run up to the invasion, in which more than 150,000 Iraqis died, and a million more were displaced.