Donald Trump has welcomed the arrest of a cleric accused of masterminding the Mumbai attacks, but faced mockery for saying it took years to find the suspect, when he is notorious for living openly in Pakistan.

Hafiz Saeed was held on suspicion of terrorist financing offences just days before Mr Trump is due to welcome Pakistan's prime minister, Imran Khan, to the White House.

The founder of the Lashkar-e-Taiba militant group has a $10m US bounty on his head for his alleged role behind the 2008 Mumbai attacks that killed 166 people.

Saeed has lived openly in Pakistan despite pressure for Islamabad to bring him to justice, and the issue has helped poison relations with Washington and Delhi. While the 69-year-old has spent time under house arrest, he has never been charged or tried.

India officials expressed scepticism that he would face justice now, suggesting the arrest had been made to appease America ahead of Mr Khan's visit to reset acrimonious relations.