Rejecting Pakistan's contention, the United States on Wednesday night said that there is need for 'direct and tough action' by Islamabad [Images] even if the perpetrators of the Mumbai terror attacks [Images] were 'non-state actors'.

"The fact is non-state actors perform from the confines of the State. There has to be direct and tough action (by Islamabad)," US Secretary of State Condoleezza Rice [Images] told a press conference after discussions with External Affairs Minister Pranab Mukherjee in New Delhi [Images].

Her remarks assume significance in the context of President Asif Ali Zardari [Images] denying Pakistan's involvement in the Mumbai attacks, saying the terror strikes were executed by the 'stateless actors', who wanted to hold the 'entire world hostage'.

Rice, who will be in Islamabad on Thursday for discussions on the issue, made it plain that 'non-state actors' were 'still a matter of your (Pakistan) responsibility that somehow relates to your territory'.

"Pakistan has to act transparently, fully and urgently," she said, while noting that "Americans understand the feelings and strong demands" in India for bringing perpetrators of the Mumbai attacks to justice.

Referring to the promise of cooperation given by Zardari in the investigations, she said, "We expect the pledges are going to be fulfilled."

On his part, Mukherjee said India was expecting Pakistan's response to the demarche issued to it and New Delhi will decide 'whatever is necessary to protect the territorial integrity and safety of its citizens'.

Noting that India has suffered repeated terror strikes in important capitals during the year, he said, 'the government is determined to act decisively' using 'all means at our disposal'.

Mukherjee said that information has been provided to Rice that the terror strikes were perpetrated by individuals who came from Pakistan and whose 'controllers' are in Pakistan.

"It is the assessment that is widely shared by the international community," the minister said.