Mr Pompeo provided no concrete evidence to support his allegations.
Iran denies al-Qaida link Iranian Foreign Minister Mohammad Javad Zarif responded to Pompeo's remarks on Twitter, calling them "fictitious declassifications" and "warmongering lies".
"Al Qaeda today is operating underneath the hard shell of the Iranian regime's protection", he said.
Pompeo said he was announcing publicly for the first time that Al Qaeda's Abu Muhammad Al Masri, accused of helping to mastermind the 1998 bombings of two USA embassies in Africa, died on August 7 a year ago.
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Au total en France, 138 351 personnes ont été vaccinées parmi les publics prioritaires définis par les autorités sanitaires. La campagne a débuté le 26 décembre dernier, sous le feu des critiques, pointant la lenteur du processus de vaccination.
However, this source said that Pompeo's rhetoric was over the top and suggested his real objective may be to sabotage US President-elect Joe Biden's expected efforts to restart the 2015 Iran nuclear deal.
Parsi also pointed out that by claiming Iran is the new home base of al-Qaida, Pompeo has set up a "casus belli that would allow the administration to go and attack Iran in its last couple of days in power".
During the speech, Pompeo announced a $7-million reward for information about Muhammad Abbatay, also known as Abd al-Rahman al-Maghrebi, who Pompeo said was believed to be in Iran.
Many experts believe that Tehran has allowed Al-Qaeda operatives to use its territory - comparatively safe from the United States military - to provide guarantees that the extremists will not target Iran.
In October 2017, when serving as Central Intelligence Agency director, Pompeo said that "there have been times the Iranians have worked alongside al-Qaeda".
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Meanwhile, the border between Canada and the United States will remain closed to non-essential travel for another month. Canada's vaccine rollout to date lags behind that of other major Western nations, according to Our World in Data .
Iran has been a target throughout the Trump administration and Pompeo has sought to further ratchet up pressure on Iran in recent weeks with more sanctions and heated rhetoric.
The majority of the perpetrators of the September 11, 2001, attacks in NY came from US-ally Saudi Arabia.
Shi'ite Iran and al Qaeda, a Sunni Muslim group, have always been sectarian foes.
Many experts believe that Tehran has allowed al-Qaida operatives to stay on its soil - comparatively safe from the USA military - as leverage to prevent attacks on Iran.
"Iran chose to allow al-Qaida to establish a new operational headquarters, on the condition that al-Qaida operatives inside abide by the regime's rules governing al-Qaida's stay inside the country", Pompeo said.
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Brent could rise to $65 per barrel by summer 2021, Goldman Sachs said, driven by Saudi cuts and the implications of a shift in power to the Democrats in the United States.
Relations between Tehran and Washington have deteriorated since 2018 when Trump abandoned Iran's 2015 nuclear deal, which imposed strict curbs on its nuclear activities in return for the lifting of sanctions.