Iran's foreign minister said Wednesday that "no tangible progress" has been made in negotiations to end the West Asia war as fresh US and Iranian strikes strained a fragile ceasefire.

Kuwaiti officials said the renewed hostilities included an Iranian drone strike on a passenger terminal at Kuwait International Airport that killed one Indian expatriate and wounded several others.

In contrast with the downbeat Iranian remarks, US President Donald Trump voiced optimism again, telling reporters at the White House, "it could happen...over the weekend."

"I hear the negotiation itself is going very well, actually," Trump said of the latest bid to end the US-Israeli war in the Middle East, which began on February 28.

However, US lawmakers dealt a political blow to the Republican president on Wednesday when the House of Representatives passed a resolution directing the withdrawal of American troops from the Iran war.

The resolution, adopted with four Republican members joining the Democrats, was largely symbolic, as the US president can veto the measure if it gains Senate approval.

"This is a loud and unambiguous message to Donald Trump on behalf of the American people: it’s time to end his deeply unpopular and illegal war of choice in Iran,” Democrats posted on X.

At a congressional hearing, US Secretary of State Marco Rubio said Iran's highly enriched uranium stockpiles were at the centre of discussions with Tehran.

Washington insists Tehran must turn over its near-weapons-grade enriched uranium, agree to curb its nuclear activities and reopen the Strait of Hormuz, the key shipping channel for Gulf oil and gas, for any peace agreement to take hold.

Iranian Foreign Minister Abbas Araghchi said lines of communication with the United States were still open but warned that any Israeli attack on the Lebanese capital, Beirut, as part of its campaign against Iran-backed Hezbollah, would trigger a "full-scale resumption" of the conflict.

"Communications with the Americans have not been cut off, and messages have been exchanged regarding the need to stop aggression against Beirut, but no tangible progress has been made in the negotiation process," the Tasnim news agency quoted Araghchi as telling Lebanon's Al Mayadeen TV.

"Any attack on Beirut will have grave consequences and will lead to a full-scale resumption of the war," he said. "Our armed forces are ready to strike Israel if it attacks Beirut."

'Playing with fire'
Kuwait's military condemned the drone strike on the airport as an act of "criminal Iranian aggression." Meanwhile, authorities from both Kuwait and India confirmed that the one fatality was an Indian national.

India's Ministry of External Affairs also condemned the attack and called for a ceasefire between both parties.

"We condemn the attack on the Kuwait International Airport today in which an Indian national has died and several of our nationals are injured. Since the onset of the conflict in West Asia, we have strongly urged that civilian population and civilian infrastructure must not be targeted. We again call upon parties to cease such attacks," the MEA said in a statement.

However, Iran's Revolutionary Guards denied attacking the airport and said it was "an error in the American Patriot systems, which landed on the terminal after failing to intercept Iranian missiles."

The Revolutionary Guards also accused US forces of provoking a response by targeting a tanker and a communications tower on the country's Qeshm Island.

The fresh attacks constitute one of the more severe tests yet of the April 8 ceasefire that paused more than a month of war sparked by the US-Israeli bombing of Iran, and has largely held despite sporadic exchanges of fire.

Trump played down the renewed hostilities, saying, "In that part of the world, ceasefire is when you're shooting in a more moderate manner."

Israeli Prime Minister Benjamin Netanyahu, meanwhile, accused Iran of "playing with fire."

"Iran surely knows what the (US) president has said, that if necessary, there'll be a full-scale return to military action," Netanyahu said in an interview with US channel CNBC.

Kuwait suspended air traffic and diverted arriving planes to other destinations following the drone attack on the airport, but later restarted Kuwait Airways flights.

The international airport has been targeted several times during the war, and had only fully resumed operations on Monday.

Israel, Lebanon agree ceasefire
In Washington, Israel and Lebanon agreed to a ceasefire after two days of direct talks. Notably, the agreement requires a "complete cessation" of fire by Hezbollah.

They further agreed "with the guidance of the United States" to create "pilot zones" in which Lebanese armed forces -- which have struggled to contain Hezbollah -- "will take exclusive control of the territory to the exclusion of all non-state actors," a joint statement said.

Further talks were planned in the week of June 22, with a view toward reaching a "comprehensive agreement."

Israel and Hezbollah, however, have continued to trade fire, with Hezbollah claiming missile attacks on northern Israel Wednesday and Lebanon saying Israeli strikes in the south killed at least nine people, including two paramedics.

Israeli troops are staging their deepest ground offensive into Lebanon in two decades.

A truce to halt the fighting in Lebanon was meant to take hold on April 17 but has never been observed.

(With AFP inputs)