Amid growing political chaos in Pakistan over the no-confidence motion against Prime Minister Imran Khan, the leader on Thursday night said he would not quit and blamed the US for the situation.
He was addressing the nation hours after the debate on the motion against him in parliament was postponed to Sunday.
Khan had been accusing opposition parties of colluding with the West to oust him. But it was the first time that he named a country.
Earlier on Thursday, Pakistan's opposition called on him to resign ahead of a parliamentary vote which could see the former cricket star ousted and the return of political uncertainty in the nuclear-armed country.
The parliament votes on whether to remove him as prime minister on Sunday at 11.30 am local time.
Khan has been facing mounting criticism of his performance, including his management of an economy beset by high inflation and rising deficits, and he lost his majority in parliament on Wednesday when a main ally quit his coalition.
"We want to send Imran Khan a message that there is no safe passage for you," said opposition leader Bilawal Bhutto Zardari.
"I want to give you a suggestion that you take an honourable exit, and an honourable exit is that you resign today and let the opposition leader take oath of the leader of the house."
In his televised speech, Khan discussed the 'threat letter' that purportedly shows "evidence" of a foreign conspiracy because he visited Russia to meet President Vladimir Putin in late February.
"I am here today because on March 8 or 7, the United States ... not the US ... we got a message. For a free country, a message like this is [not only] against its prime minister but is also against the country [itself]", he was quoted by the Dawn newspaper as saying.
"They knew beforehand that a no-trust move was coming. The no-trust motion was not even submitted [at the time]. It means that they (the opposition) was connected with these people abroad; they say they are angry with Pakistan ... they make this excuse,” Imran said.
They say, the PM said, they will forgive Pakistan if Imran Khan loses in no-trust move, but if the move fails, Pakistan will have to go through a difficult time."
"In an official document it was said that 'if Imran Khan remains the prime minister, our ties will suffer and you will face difficulties…. They said that Imran Khan decide to go to Russia on his own even though the Foreign Office and the military leadership was consulted,” he added.
"Our ambassador told them that the decision [to visit Russia was made after consultations] but they are denying it and saying that 'it was only because of Imran Khan and that our ties cannot be good if he stays.' What they are actually saying is that they have no issue with the people who will replace Imran Khan."
On Wednesday, Khan's main parliamentary ally, the Muttahida Qaumi Movement, abandoned his coalition and threw its lot in with the opposition seeking to oust him.
Khan's ouster could mean another round of instability in a country in which the military has a long record of intervening in politics and no prime minister has ever completed a full five-year term.