The United States has said that it will be good if Pakistan shifts to a tougher approach towards the Lashkar-e-Tayiba, the prime suspect in the Mumbai terror attacks [Images].

"We're continuing to follow the reports. What we are looking to see, if there's going to be a shift in Pakistan into how they deal with the LeT," White House Press Secretary Dana Perino [Images] said.

"And if it proves out, over time, that there is that shift, then that would be a good one and something that we would welcome. But it's just -- it's just too early for us to say," she said.

On the reports of arrests of some suspects in Pakistan, Perino said, "We are following those reports very closely.... I couldn't tell you definitively if all of what's been reported is accurate."

Her comments came after Pakistan Prime Minister Yousuf Raza Gilani [Images] said that two top LeT commanders Zakiur Rehman Lakhvi and Zarar Shah have been taken into custody for investigation.

"We continue to urge the Pakistanis and the Indians to work together to get to the bottom of who was responsible for these attacks and, most importantly, to try to prevent follow-on attacks for anyone that was left over," Perino added.

Meanwhile, State Department Spokesman Sean McCormack also asked Pakistan to ensure that its territory is not used to launch a Mumbai-like attack in the future.

"There's a law enforcement angle here, which refers to making sure that people who are responsible for these attacks and the deaths of innocent people are brought to justice.There's also another aspect to this, that you use those opportunities also to help prevent future attacks," McCormack said.

The diplomat described the reported crackdown on terror outfits by Islamabad [Images] as 'serious and important steps'.

"...You need to lever what you have done to prevent future attacks. That is critically important. It's important for Pakistan, it's important for India, it's important for the region. Frankly, it's important for us. And I think Secretary Rice made that clear. So this is something that countries around the world that face the threat, whether internally or externally, need to engage in every single day," McCormack said.

Noting that India was going through the same situation the US had experienced after the 9/11 attacks, he said that Washington was ready to help New Delhi [Images] in building up the right institutions and right linkages to prevent terrorist activities.

Asked about further actions from Pakistan, he said, "Let's see what the next steps are. I have outlined in principle what we believe the next steps are. I'm not prepared at this point to prescribe anything in particular."

"I think the Pakistani government has a healthy appreciation of the situation and the threat that these violent extremist groups pose not only to Pakistan, but also to its neighbours," McCormack added.