US President-elect Joe Biden announces his national security nominees and appointees, at his transition headquarters, in Wilmington, Delaware, Nov. 24, 2020. Photo: Reuters / Joshua Roberts.

i24News – US President-elect Joe Biden stressed Thursday night it would be “hard to tell” to what extent the killing of Iranian scientist Mohsen Fakhrizadeh will complicate his dealing with Iran, reiterating his preference to rejoin the 2015 nuclear deal.

“The bottom line is that we can’t allow Iran to get nuclear weapons,” Biden told CNN.

But the Democrat criticized outgoing President Donald Trump’s handling of the Iranian issue, stipulating his decision to pull out of the Iran nuclear deal in 2018.

“He has pulled out to get something tougher, and what have they done?” Biden asked.

“They’ve increased the ability for them to have nuclear material. They’re moving closer to the ability to be able to have enough material for a nuclear weapon. And there’s the missile issues,” he added.

The president-elect further told CNN that “All those things, I think, are going to be very difficult. But I know one thing: We cannot do this alone. And that’s why we have to be part of a larger group, dealing not only with Iran, but with Russia, with China and a whole range of other issues.”

Former US President Barack Obama, under whom Biden served as the Vice President, led diplomatic efforts with Tehran, which resulted in the 2015 nuclear agreement co-signed with the UK, Germany, France, Russia and China.

Under the accord, Iran agreed to limit its sensitive nuclear activities and permit international supervision over its nuclear project in exchange for the lifting of economic sanctions.