The US House of Representatives has approved a defence bill with amendments to delay the lifting of Don’t Ask, Don’t Tell.

The Defense Authorization Bill was approved in a 322 to 96 vote yesterday.

The amendments require the chiefs of all four military services to certify that the change won’t hurt military readiness, something gay rights campaigners say is a deliberate effort to slow down the repeal effort.

They also require the four chiefs of the military to declare that gay marriages cannot take place on military grounds and that military chaplains cannot perform the ceremonies.

The 18-year-old ban on openly gay troops is expected to be lifted this summer.

Currently, a repeal bill signed by President Obama only requires the president, defence secretary and joint chiefs of staff chairman to certify it will not harm the military.

However, Republican lawmakers argued that President Obama has never served in the military, Admiral Mike Mullen has never served in ground combat and defence secretary Robert Gates was a political appointee.

This week, the White House said it opposed any measure on DADT which would “create uncertainty for service members and their families”.

It is unclear what effects the amendments will have if they are ultimately approved.

Alexander Nicholson, the executive director of Servicemembers United, said they “should not become a cause for concern as long as our allies in the Senate and the President all stand strong” and refuse to support the bill.

He added: “These amendments were nothing short of a waste of time by lawmakers who were sent to Washington to do serious business and a waste of taxpayer money. “