Afghan President Hamid Karzai departed Tuesday for a two-day diplomatic trip to India, a visit that comes amid increasing tension with Pakistan, a traditional foe of both countries.

President Karzai will meet with Indian Prime Minister Manmohan Singh in New Delhi, where the two leaders are expected to boost economic ties.

Mr. Karzai and Mr. Singh could also sign a deal that calls for India to increase its training of Afghan security forces.

India, which has already pledged $2 billion in aid to Afghanistan since the start of the U.S.-led invasion in 2001, is eager to expand its regional influence and prevent the spread of unrest as NATO troops pull out of the country by the end of 2014.

Both Indian and Afghan authorities have accused Pakistan of creating unrest in Afghanistan, a charge that Pakistan denies.

On Monday, Mr. Karzai again accused Pakistan of playing a “double game” in dealing with extremists. Afghanistan's intelligence agency says it has evidence that last month's killing of former Afghan president Burhanuddin Rabbani was planned in Pakistan.

India also accuses Pakistan of plotting attacks on Indian targets within Afghanistan, including two bomb attacks on its embassy in 2008 and 2009.

The United States has accused Pakistan of having “links” with the Haqqani network, an al-Qaida-affiliated Afghan militant group, which Washington says has safe havens in Pakistan's North Waziristan region.

Last week, the outgoing chairman of the U.S. Joint Chiefs of Staff, Admiral Mike Mullen, called the Haqqani network a “veritable arm” of the ISI, Pakistan's main intelligence agency.