March 29 (UPI) — Iran’s parliament speaker, Mohammad Bagher Ghalibaf, issued a warning Saturday against a possible ground troop invasion as the U.S. military sends more troops to the region.

Ghalibaf made the comments in a message marking 30 days since the start of the war. The United States and Israel began strikes on Iran on Feb. 28 in their efforts to diminish the country’s nuclear weapons program.

Ghalibaf accused the United States of secretly planning a ground invasion of Iran. On Saturday, two U.S. ships arrived in the region carrying 3,500 U.S. service members as well as fighter jets, transport aircraft, amphibious assault vessels and other tactical assets. More troops were expected, U.S. Central Command said.

“The enemy publicly sends messages of negotiation while secretly planning a ground invasion — unaware that our men are waiting for American troops to enter on the ground, ready to unleash devastation upon them and punish their regional allies,” Ghalibaf said, as reported by CNN.

Last week, the Trump administration proposed a 15-point peace plan with Iran. President Donald Trump also ordered a 10-day halt on strikes against Iranian energy sites, though Israel carried out its own attacks on energy sites Friday.

Secretary of State Marco Rubio said Friday that Iran had not responded to the peace proposal.

“The United States speaks of its aspirations, presenting what it failed to achieve in war as a 15-point list to pursue through diplomacy,” Ghalibaf said.

“As long as the Americans seek Iran’s surrender, the answer of your sons remains clear: ‘Far be it from us to accept humiliation.'”

Ghalibaf’s message came in the wake of a Saturday report by The Washington Post that the Defense Department has drawn up plans for a weeks-long ground operation in Iran. Officials told The Post the plan isn’t considered a full-scale ground invasion, but would involve Special Operations forces and infantry troops.

White House press secretary Karoline Leavitt issued a statement in response to the possibility of ground troops in Iran.

“It’s the job of the Pentagon to make preparations in order to give the commander in chief maximum optionality,” she said. “It does not mean the president has made a decision.”

Iran has launched attacks on Israeli and other U.S. allies in the Persian Gulf region, including one Sunday on a military camp in Kuwait, which killed 10 Kuwaiti service members. The army said it detected 14 ballistic missiles and 12 hostile drones in Kuwaiti airspace over the previous 24 hours. Since the start of the war, it has monitored more than 300 ballistic missiles, 2 cruise missiles and more than 600 hostile drones.

Meanwhile, Israeli officials said emergency officials were working on a large fire that broke out at a hazardous materials factory at the Neot Hovav industrial complex, The Guardian reported. The Israeli military blamed “a weapon fragment or interceptor fragment” for the damage and fire.