The ongoing shelling in Afghanistan's eastern Kunar province is putting relations with Pakistan under strain, Afghan Ministry of Foreign Affairs (MOFA) spokesman Janan Mosazai said Sunday.

Amid claims that the missiles being launched from Pakistan into Afghanistan have increased since Pakistan's Prime Minister visited last week, the Afghan government sought to address criticism it is not doing enough to stop the attacks.

While Mosazai spoke on the matter at a press conference in Kabul, the MOFA released a statement that the Deputy Foreign Minister Jawed Ludin had met with Pakistan's Ambassador received Mohammad Sadiq on Sunday afternoon.

Ludin spoke to Sadiq of "the Afghan government's serious concerns regarding the recent reported artillery shelling against several villages in Kunar province from across the Durand Line. The most recent shelling on the night of July 20 against villages in Kunar province killed three men and a woman and injured several other civilians," the statement said.

Ludin warned that the continuation of such shelling against could have a significant negative impact on bilateral relations, "especially in light of the broad range of important issues related to peace, security and economic cooperation that both sides need to focus on."

According to MOFA, the pair agreed to convene a senior-level meeting of military officials from both countries in the near future in Jalalabad to discuss the shelling and improve military-to-military coordination along the Durand Line.

Meanwhile, Mosazai said that Afghanistan's National Security Council has started serious investigations into the attacks, saying that any continuation of them were not acceptable to the Afghan government.

"Continuation of shelling in the eastern parts of Afghanistan from Pakistan's soil will not benefit the close cooperation of Afghanistan and Pakistan," Mosazai added.

On other matters, Mosazai said that Afghanistan and Iran had come to an agreement on the exchange of prisoners, with a deal recently signed.

"A bilateral agreement on prisoner exchange between Afghanistan and Iran was recently signed between the countries. The two countries can exchange prisoners based on certain procedures," Mosazai told the reporters.

He also accused the Pakistan government of not cooperating in transporting Afghan school books which are still delayed in Pakistan after being caught up in the impasse over the Nato supply lines, but he added he was optimistic the books would be transferred to Afghanistan soon.