Senior Pakistan Tehreek-e-Insaf (PTI) party leaders stand for the national anthem before a press conference in Islamabad on Friday, amid claims of alleged vote-rigging in Pakistan's national elections. AFP

The United States is concerned about reports of intimidation and voter suppression in Pakistan's election, the White House said on Thursday after reports of protests in some parts of the country.

Pakistan's election last week did not return a clear majority for anyone but independent candidates backed by jailed former Prime Minister Imran Khan won 92 out of 264 seats, making them the largest group.

Questions have been raised about the fairness of the Feb. 8 election both inside Pakistan as well as in major foreign capitals, with Washington having previously said there were "undue restrictions" on freedoms of expressions and assembly.

Supporters of the Grand Democratic Alliance gather for protest against results of the polls in Jamshoro, Pakistan.

"We are watching this very, very closely," White House spokesperson John Kirby told reporters on Thursday, expressing concern about "intimidation and voter suppression."

"International monitors are still taking a look at those tallies, I'm not going to get ahead of that process," he added about the vote count.

The two forms have been at the centre of the controversy surrounding poll results in Pakistan.

At the heart of the controversy have been Forms 45 and 47, meant to provide official documentation of election results.

Supporters of different political parties chant slogans during a protest in Quetta, Pakistan. AFP

The Election Commission of Pakistan (ECP) provides several forms to document results in a constituency. Most important of these is Form 45, also known as the ‘Result of Count’ form.

These results have now been challenged in Pakistani courts.

Agencies