Mottaki blamed the US for destabilising the situation in Pakistan and Afghanistan, saying the presence of US troops in the area poses a threat to Iran's security.
Speaking to a Pakistani media delegation in Teheran, he said, "An increase in the number of US troops in Afghanistan could create a new crisis for the whole region in 2010 and we are holding (US President) Barack Obama responsible for that crisis".
Responding to questions from the Pakistani journalists, Mottaki said Afghanistan has become more unsafe and problematic after US troops arrived in the region in October 2001.
"US forces are bombing wedding parties and killing innocents in Afghanistan," the Iranian foreign minister said. "They are not bothered with the fact that poppy production has reached over 8,000 tonnes a year despite their presence in Afghanistan -- it was only a few hundred tonnes in 2001. They cannot resolve problems; they can only increase problems."
The foreign minister claimed that Iran was well on the road to progress in spite of the stringent US-led sanctions imposed due to the country's refusal to disclose details about its nuclear programme.
Obama has sought international legislation to impose sanctions on non-Iranian companies that are involved in Iran's energy sector. If enacted, this legislation will force many foreign companies to halt their business dealings with Iran. It will particularly hit Pakistan and China which are aggressively promoting their interests in Iran.
Mottaki expressed concern about the poor law and order situation in the Pakistani and Iranian parts of Baluchistan. Jindullah, a terrorist outfit led by Abdul Malik Ragie, has been held responsible for bomb blasts and kidnappings in Iranian Baluchistan. This group has some safe havens in Pakistan, the foreign minister noted.
Iran has blamed Jindullah for carrying out a suicide attack in Sistan, Iran, that killed 42 people, including top officers of the country's elite Revolutionary Guard, last October.
"We expect Pakistan to either take action against this terrorist group as soon as possible or start a joint operation with us against them or allow us to take action against them in Pakistan," Mottaki said.
The minister added that Iran would not launch a unilateral operation in Pakistani Baluchistan without obtaining prior permission from Islamabad. He alleged that "some powers" are trying to create misunderstandings between Iran and Pakistan without clarifying their identity.
Mottaki also mentioned the kidnapping of Iranian diplomat Heshmatollah Attarzadeh who was abducted from Peshawar on November 14, 2008.
"The Iranian parliament has called me ten times to explain why Pakistan has failed to rescue the kidnapped diplomat; why Pakistan has failed to destroy Jindullah's hideouts in Baluchistan," Mottaki said.
"I am trying my best to downplay the tension (between the two nations) because it will benefit only our common enemies," he added.
The minister stressed that ensuring stability in the Iranian and Pakistani sections of Baluchistan was a pre-requisite to ensure the success of the ambitious gas pipeline project visualised between India, Iran and Pakistan.
He claimed that Iran was ready to start the pipeline project. Though Pakistan and Iran have finalised their aspects of the $7 billion project, India still needs some more time to make up its mind, he said.
"We can start the gas pipeline without India," Mottaki declared and blamed the US for trying to sabotage the enterprise.
Sounding a note of caution about India, Mottaki said, "The growing relations between the US and India should not affect the relations India has with other countries in the region."
He expressed confidence that Pakistan, a key US ally, would not hesitate to commence the project with Iran despite American pressure.
"We must not allow any third country to interfere in the bilateral relations of Iran and Pakistan," Mottaki said.
In a statement bound to make New Delhi wary, the minister declared, "China might join the pipeline project with Iran and Pakistan very soon."
Mottaki pointed out that Pakistan President Asif Ali Zardari has visited Iran twice in the last 20 months. Iranian President Mahmoud Ahmadinejad, who has also visited Pakistan, is planning another visit.
"We will sign new agreements for cooperation in defence, intelligence cooperation, trade and commerce during the Iranian president's visit to Pakistan," the minister added.