Amid concerns by certain quarters in Pakistan over the "strings" attached to US aid, a key Congressional bill that triples American financial support to Islamabad to USD 7.5 billion in next five years has been challenged in the Supreme Court.

A petition filed by Zafar Ullah, chief of Watan Party in Lahore Registry of Supreme Court pleads that the Kerry-Lugar Bill, which was approved by the US Congress, compromises Pakistan’s sovereignty, the Online news of Pakistan reported today.

It also alleged that the government is taking decisions without taking parliament into confidence, the reported said, adding a referendum could have been held on this important issue.

Pleading that the Court direct the government to stop implementation of the US law, it claimed the bill could be declared null and void under Article-17 of the constitution, as it was against country’s integrity.

Both the military and the mainstream opposition parties have expressed serious reservations on the bill, the report said.

However, top US officials have said that there was an attempt to "willfully distort" facts related to the legislation.

Richard Holbrooke, Special Representative to Afghanistan and Pakistan, has said the bill requires only reporting by the executive branch –- the Obama Administration -- on progress toward long-term security and stability in Pakistan.

The 2010 Defense Authorisation Bill, which was passed by the Senate and the House of Representatives, provides for a military assistance of USD 2.3 billion to Pakistan in one year, in addition to the USD 1.5 billion non-military aid per annum for the next five years as approved by the Kerry-Lugar Bill, which was signed into law by US President Barack Obama early this month.

"There are no conditions in this bill. I don't want to get into legalisms here, but there are requirements on us," Holbrooke said in Washington.