In the backdrop of Jaipur serial blasts, Prime Minister Manmohan Singh [Images] on Saturday said terrorists want to prevent normalisation of Indo-Pak relations and that an effective strategy needed to be adopted to defeat such "nefarious designs."

"There is no doubt that terrorist elements have many objectives -- to disturb the atmosphere of communal harmony in our country, to create communal disturbances and also to prevent normalisation of relations between India and Pakistan," he told reporters in Bagdogra after wrapping up his two-day visit to Bhutan.

"We have to be mindful of these nefarious designs and we have to adopt effective strategy to counter all these dangers," Dr Singh added.

He was responding to a question whether the Jaipur serial blasts had vitiated the atmosphere ahead of the Indo-Pak talks in Islamabad on May 20-21.

The foreign secretary-level talks on May 20 followed by foreign ministerial talks the next day will mark resumption of the composite dialogue after more than seven months.

In the backdrop of the Jaipur blasts, terrorism will top the agenda of the talks, with India expected to raise its concern over continued infiltration from Pakistan.