"I am confident that my visit to the Maldives and Sri Lanka will further strengthen our close and cordial ties with our maritime neighbours, in line with our 'Neighbourhood-First Policy' and the vision of security and growth for all in the region," the prime minister said.
It is learnt that the Maldives will honour Modi with the Order of Nishanizzuddeen, a prestigious award.
In a pre-departure statement, he said his visit to Sri Lanka is to express India's solidarity with the government and the people of the island nation in the wake of the "terrible terrorist attacks" there on April 21.
"The people of India stand firmly with the people of Sri Lanka, who suffered great agony and destruction in the wake of the horrific terror attacks on Easter. We fully support Sri Lanka in the fight against terror," he said.
Sri Lanka was hit by a wave of bombings on Easter Sunday in which over 250 people were killed.
Modi will be the first head of government to visit Sri Lanka after the dastardly attacks.
About his visit to the Maldives, Modi said India considers the country as a valued partner with whom it shares deep bonds of history and culture.
"Our bilateral relations with the Maldives have been greatly strengthened in the recent past. I am confident that my visit will further deepen our multi-faceted partnership," he said.
The prime minister visited the Maldives in November to attend President Ibrahim Solih's swearing-in ceremony.
The relations between India and the Maldives deteriorated after the then President Abdulla Yameen imposed emergency on February 5 last year. However, ties were back on track under Solih's presidency.
On Saturday, Modi will address the Parliament of the Maldives.
Since June 2014, Modi addressed parliaments of 10 countries including Bhutan, Australia, Fiji, Mauritius, Sri Lanka, Mongolia, Afghanistan, the US (Congress) and Uganda.
Officials said a slew of MoUs are expected to be signed including budgetary support by India for development projects in Maldives.
Both Modi and the Maldivian President will jointly inaugurate two defence-related projects - a coastal surveillance radar system and composite training centre for Maldives National Defence Forces (MNDF).
On Sri Lanka, Modi said India's ties with it have gained considerable momentum in the last few years.
Sri Lankan President Maithripala Sirisena visited India last week to India Modi's swearing-in ceremony.
"I look forward to meeting the Sri Lankan leadership during my visit," Modi said.
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