ISLAMABAD, Pakistan — Pakistan’s defense minister told Parliament on Monday that Saudi Arabia had asked Pakistan for aircraft, warships and soldiers to join its offensive against the Houthis in Yemen, possibly signaling Saudi plans to expand its war there.
The Saudi government, backed by other Persian Gulf countries and the United States, started its campaign against the Houthis in late March, relying primarily on air power. But weeks of airstrikes have failed to stop the Houthi advance, including into the port city of Aden, Yemen’s second largest city, in recent days.
The Saudis and their allies have repeatedly raised the possibility of a ground invasion, which analysts say would most likely rely heavily on foreign troops, including those from close Saudi allies like Pakistan or Egypt.
In Parliament on Monday, Khawaja Muhammad Asif, the defense minister, did not say when or where the Saudis wanted Pakistani troops deployed. Aitzaz Ahsan, an opposition politician with the Pakistan Peoples Party, asked the government to clarify its position on the Saudi appeal.
“You have told us that the Saudi king requested troops and air force for the strikes,” Mr. Ahsan said. “But you didn’t inform us what was the response by the government on this request.”
Saudi officials have framed their military intervention as an effort to weaken the Houthis in order to restore Yemen’s exiled president, Abdu Rabbu Mansour Hadi, to power.
Critics of the Saudi action have called the offensive a strategic mistake. They say the intervention is driven by an erroneous Saudi view of the Houthis as an Iranian proxy force, and has exacerbated Yemen’s civil conflict while exacting a crushing humanitarian toll on the region’s poorest country.
Hundreds of people have been killed by Saudi airstrikes or in clashes between rival militias. Yemen’s powerful Al Qaeda affiliate has capitalized on the chaos by taking control of Al Mukalla, a southern Yemeni city, which the militants have been able to hold, unopposed, for four days. Fuel, food and medical supplies to civilians trapped by the fighting were dwindling as aid agencies struggled to gain access to the country.
Pakistan has a long history of military cooperation with Saudi Arabia that stretches back decades. It has provided extensive military training to the Saudis and stationed tens of thousands of troops in the kingdom, including during the 1990-91 Persian Gulf war.
In the latest sign of how the Saudi intervention had inflamed the civil conflict, members of Yemen’s most prominent Islamist party, Islah, said Monday that the Houthis had abducted hundreds of their members over the last few days.
Haroon al-Wesabi, director of the Sana Rights Center, which is seen as close to Islah, said the crackdown followed a declaration by Islah that it was supporting the Saudi-led military action. In the past two days, he said, Houthi gunmen stormed Islah’s party headquarters, as well as homes of its leaders and members, abducting 318 people in at least six Yemeni provinces.
Mr. Wesabi said that it was unclear where the detainees were being held, noting that the crackdown was still underway.
The abductions added to longtime complaints about the way the Houthis have treated their perceived adversaries as they have gained power. Critics have accused them of harassing journalists and political opponents and, more recently, using indiscriminate force in their drive to capture Aden, endangering civilians.
In an interview, a member of the Houthi’s senior political leadership, Mohammed al-Bukhaiti, did not deny the abductions, saying they were carried out for “security reasons.”
“Islah did not only support the aggression,” Mr. Bukhaiti said, referring to the Saudi offensive, “but also maximized its readiness to move militarily against the country by acting like a fifth column.”
He added, “The crackdown has come to eliminate any military move targeting the country.”