President Donald Trump warned that fighting with Iran could continue for an extended period, saying Tehran’s military capabilities would gradually weaken under continued U.S. strikes.

Trump said Iran still has some ability to retaliate despite major losses to its military forces and admitted he is less confident about reaching a diplomatic agreement.

The comments came after renewed U.S. strikes on Iranian military targets following attacks on American forces and regional shipping.

Efforts to revive a previous ceasefire agreement have stalled over issues including Iran’s nuclear program, sanctions, and control of the Strait of Hormuz, Fox News has reported.

The ongoing conflict has created uncertainty over when the fighting will end as pressure grows on the Trump administration ahead of the November midterm elections.