Sweden's foreign office has been unable to contact its embassy in Pakistan since president Pervez Musharraf declared emergency rule in the country on Saturday.
The Swedish ambassador in Islamabad, Anna Karin Enestrom, was in Dubai as Pakistan is locked in constitutional crisis, Swedish news agency TT reported, quoting foreign ministry officials.
"Both she and I have tried to get hold of the deputies at the embassy but we have not succeeded. I don't know if the telephone lines are working properly," said Sofia Karlberg at the Ministry of Foreign Affairs.
Foreign minister Carl Bildt viewed developments in Pakistan as "seriously worrying."
"We have not been able to establish contact with the embassy there. It's clearly a serious situation," said Bildt.
"There's not necessarily any immediate danger for Swedes, but there is a risk that confrontations and conflicts in the country will escalate. It is therefore worth emphasizing clearly the recommendation not to travel to Pakistan."
Sweden's immediate response was to focus on its consular activities, ensuring that all Swedes in Pakistan are contacted. There are around 200 Swedes in the country. According to the Ministry for Foreign Affairs they are spread out across the country.
However, Bildt said it was too early to say that Swedes should leave Pakistan.
Chief of Army Staff of Pakistan General Pervez Musharraf declared on Saturday a state of emergency in the country and issued a provisional constitutional order.