BANNU: A bomb planted by Taleban insurgents ripped through a vehicle carrying Pakistani troops on Sunday, killing 20 soldiers and prompting Prime Minister Nawaz Sharif to cancel his trip to the World Economic Forum in the Swiss resort of Davos this week.

At least 30 others were wounded as the convoy prepared to leave the volatile northwestern town of Bannu for nearby North Waziristan, a lawless, tribal region on the Afghan border where many Al-Qaeda-linked militant groups are holed up.

The army said the bomb had been planted in a civilian vehicle rented locally in order to transport troops to North Waziristan. The device exploded as soldiers got inside the car and prepared to leave.

“With the help of God we claim responsibility for this,” Pakistani Taleban spokesman Shahidullah Shahid said in a telephone call from an undisclosed location. “The army is our enemy. We will carry out many more attacks like this.”

Sharif condemned the attack and canceled his trip to the Davos gathering which runs from Jan. 22 to 25 and draws thousands of the world’s most influential people.

“Our nation is united against extremism and terrorism and the sacrifices rendered by our citizens and personnel of law enforcing agencies will not go in vain,” he said in a statement.

“The fact is that we have neither refused dignified, serious and meaningful talks in the past, nor will we deny the importance of negotiations in the future,” Azam Tariq, a Pakistani Taleban spokesman, told Reuters Television on Friday.