WASHINGTON — US President Donald Trump said on Friday that the United States was not involved with a failed Iranian rocket launch, and he wished Tehran luck at finding out what went wrong.

"The United States of America was not involved in the catastrophic accident during final launch preparations for the Safir SLV Launch at Semnan Launch Site One in Iran," Trump said on Twitter.

The rocket exploded on its launch pad at a space center in northern Iran on Thursday, an Iranian official said. A US official also said Iran suffered a satellite launch failure.

The United States has warned Iran against rocket launches, fearful the technology used to put satellites into orbit could enable Tehran to develop the ballistic missile capability needed to launch nuclear warheads.

Tehran denies the US accusation that such activity is a cover for ballistic missile development.

The Trump administration has ratcheted up economic pressure on Iran with a series of economic sanctions to try to force it to renegotiate a pact reached with world powers in 2015 limiting its nuclear program.

Trump has offered to hold talks with Iran but Tehran says first it must get relief from US sanctions. — Reuters