"Nobody has the power to halt this project," Mr Zardari said during an interaction with senior editors and TV anchors at his private residence in Lahore late last night.
Pakistan, he said, is a sovereign and independent country that it acting in its national interests by going ahead with the pipeline.
The pipeline will be formally inaugurated on March 11 in Iranian city of Chahbahar and dignitaries from regional countries have been invited to the event, Mr Zardari said.
Asked about US opposition to the project, Mr Zardari said Pakistan can make decisions independently and sign an agreement with any country to tackle its energy crisis. He expressed the hope that with time, critics of the project will appreciate Pakistan's growing energy needs and the requirement of the pipeline.
"Pakistan does not want confrontation with anyone and firmly believes that negotiations and dialogue are the best tools to create greater understanding of issues," he said.
The US State Department warned last week that the pipeline could attract sanctions.
"It's in their (Pakistan's) best interests to avoid any sanctionable activity, and we think that we provide and are
Providing a better way to meet their energy needs," said spokesman Patrick Ventrell.
Mr Zardari said he intended to take up the issue of the pipeline with the US administration. During his recent visit to Tehran, he met his Iranian counterpart Mahmoud Ahmadinejad and Supreme Leader Ayatollah Ali Khamenaei and both sides agreed on the need to expeditiously complete all mega projects, including the gas pipeline.
The President also defended Pakistan's decision to hand over the operation of the Gwadar deep sea port to China and dismissed India's concerns in this regard.
During the interaction, the president also spoke on the upcoming general election and said "some political parties" were dependent on and lenient with "non-state actors".
Democracy is in strong hands and the non-state actors would weaken as political parties became stronger, he said.
Though Zardari did not name the non-state actors or their supporters, his remarks were apparently aimed at the PML-N, which rules Punjab province and has been criticised for its reluctance to crack down on the banned Lashkar-e-Jhangvi that has claimed several recent attacks on Shia Hazaras.
Reports have said that the PML-N has reached an understanding with the Ahl-e-Sunnat Wal Jamaat, considered a front for the LeJ, for the upcoming polls.
Mr Zardari said the general election would be fair and free and held on time. He said the party that wins most seats in parliament will be invited to form the next government. The implementation of constitutional articles for clearing candidates will ensure that "clean" persons contest the polls, he added.
"I will transfer power to the party that wins a majority in the National Assembly. I hope the Pakistan People's Party will perform well in the elections," he said.
Referring to one of his predecessors who has been criticised for his controversial decisions, Mr Zardari said, "The presidency was a base for conspiracies during the period of Ghulam Ishaq Khan in the 1990s but let me tell you that I will not become the Ghulam Ishaq Khan of 2013. I'll swear in any government formed as a result of the elections."
Former premier Yousuf Raza Gilani will lead the PPP's campaign and address rallies and meetings, Mr Zardari said.
The PPP-led government will complete its five-year term on March 16 and leaders of the ruling party have said that the general election is expected to be held by mid-May.