The Bush administration has lauded Pakistan President Pervez Musharraf's [Images] anti-terrorism efforts, saying he is an "extremely valuable ally" who is taking "considerable" political risks by joining the war against terror.

"We understand that the hunt for -- Osama bin Laden and others... have been filtering across borders. And we understand the obligations of sovereign governments, and we're working with General Musharraf -- President Musharraf -- to do what he can," White House Spokesman Tony Snow said in response to a query.

"He's been very helpful in the war on terror, and he's taking considerable political risks to do so. We appreciate that. He is an extremely valuable ally in the war on terror, and we consider him such," the spokesman added.

The Bush administration has defended Musharraf's role in the ongoing war on terror and appreciative of his efforts in tracking down the Taliban and the al Qaeda but often taking note of Musharraf "sticking" his neck out in the process.

But critics of the Bush administration and the war on terror do not give unquestioned credit to Islamabad and question the extent to which Musharraf has been a so-called valuable ally in the war against terror.

In recent days Islamabad has taken a lot of flak for striking a deal with the northern tribal chiefs which has been seen in some quarters as a sign of a softened approach on terrorism and weakening in the efforts to nab the al Qaeda chief widely believed to be hiding in Pakistan most of the time.