The United States has launched a massive billion dollar expansion of its embassy in Islamabad, a top US diplomat confirmed here but vehemently denied spate of media reports and political alarm that there are some hidden objectives.

“The government of Pakistan is on board and understands entirely what is the requirement for an expanded mission and they support it,” US Chargé d’Affaires Gerald Feierstein told reporters here in a briefing.

The subject came up for heated discussion in the Parliament with leader of the opposition, Chaudhry Nisar Ali Khan, voicing strong concern about American intentions and asked the Prime Minister to take the house into confidence.

Khan also referred to reports which claimed US was adding 1,000 Marines to be located in the revamped embassy and feared that there could be some “insidious designs” behind stationing of such unusually large force here.

Gerald Feierstein admitted there is going to be a big increase in the staff but said the increase in marine strength wouldn’t be “as dramatic as being suggested by the press.” But he did not confirm the precise strength of Marines.

The US diplomat insisted that the increase in staff had been necessitated by the rise in American assistance to $1.5 billion a year for next five years under Kerry-Lugar bill.

“When you have got non-military and economic assistance going up to $1.5 billion every year and the security aid almost trebling, then you need people to develop, implement and run the programmes and, more importantly, keep an oversight to ensure that money is appropriately spent.”

He said the matter had been discussed with the government and the US “believed that the Pakistan government understands that in order to manage the new programmes, the embassy has to grow”.

The embassy’s current staff strength is already beyond the sanctioned level. The Chargé d’Affaires explained that there were 250 permanent employees, and the others were on short-term assignments ranging from a few weeks to months.

Answering questions, Feierstein had no plausible explanation for the $112.5 million Marine residential complex to be built inside the embassy premises, indicating that their number may run into hundreds.

He said that the Marine House would be used as residential quarters of the Marines posted in Islamabad and insisted it wouldn’t be a hi-tech facility. Regarding the huge amount of money earmarked for the facility, he said: “That’s the way people budgeted it.”