In Brussels, Modi will attend the long-pending India-EU summit. He will also hold a bilateral summit meeting with his Belgian counterpart Charles Michel where ways to deal with terrorism will form a "very important part".
The India-EU Summit is aimed at deepening the strategic partnership between the two sides which are likely to deliberate on ways to finalise the free trade agreement. The last Summit had taken place in 2012.
India-EU ties witnessed some strain after the 28-member bloc had not responded to New Delhi's proposal for a brief visit by Modi to Brussels, the EU headquarters, during his trip to France, Germany and Canada in April last year.
"The attacks in Brusels, of course, will be a very important part of the discussions. In fact, it will be the starting point of the talks," Joint Secretary (Europe) Nandini Singla, told reporters.
In Brussels, Modi will meet top businessmen, including a delegation of diamond traders, and will also address the Indian diaspora. He will also meet Parliamentarians and a delegation of indologists, separately.
Antwerp in Belgium is the largest diamond trading hub globally as about 84 per cent of the world's rough diamonds passes through there. There is a sizeable presence of Indian traders in Antwerp.
From Brussels, Modi will leave for Washington to attend the 4th Nuclear Security Summit (NSS) on March 31 and April 1 where he will be making some specific announcemnents and proposals with regard to nuclear security.
India will submit a national progress report on nuclear security at the summit, which is also expected to deliberate on ways to tackle nuclear terrorism.
Asked whether Modi will meet his Pakistani counterpart Nawaz Sharif in Washington, External Affairs Ministry Spokesperson Vikas Swarup did not give a direct answer and only said it was usual for leaders to meet their counterparts on the margins of international meets.
From Washington, Modi will travel to Saudi Arabian capital Riyadh on April 2 for a two-day visit at the invitation of King Salman Bin Abdulaziz Al-Saud.
Saudi Arabia has become India's fourth largest partner with bilateral trade exceeding USD 39 billion in 2014-15. It is also India's largest crude oil supplier and accounts for about one-fifth of total imports.
There are over 2.96 million Indian nationals working in Saudi Arabia, the largest expatriate community in the country.
This is the highest-level visit from India to Saudi Arabia after the then Prime Minister Manmohan Singh trip in 2010.
Modi will hold discussions with the King on a range of key issues including expanding counter-terrorism mechanism as well to step up ties in energy, trade and investments. Both sides will sign a number of MOUs following talks between the two leaders.
Signalling growing cooperation in the fight against terror, Saudi Arabia has deported a number of terrorists to India in the last few years including 26/11 accused Abu Jundal.
There is an exisiting counter-terror mechanism between India and Saudi Arabia and both sides are likely to enhance it further.
Welfare of Indian community as well as Haj pilgrimage are likely to figure in talks. The King will also host a lunch for Modi which will be attended by key ministers and officials.
In Riyadh, Modi will meet top CEOs of Saudi companies, visit the famous Masmak fort, will interact with the Indian community and visit Tata Consultancy centre which had trained over 1,000 Saudi women. It is perhaps first such IT training centre.
Modi will also meet Indian workers of a project being implemented by L&T.
The 'Strategic Partnership' established through Riyadh declaration in 2010 envisions a deeper engagement in political, economic, security and defence areas.
Saudi Arabia plans to invest USD one trillion in infrastructure development over the next five years and Modi is likely to pitch for participation of Indian companies in the projects.
In Brussels, Modi and Charles will be "technically activating" the largest optical telescope of its kind in Asia located at Devasthal near Nainital. The telescope is a product of Indo-Belgian collaboration.
The two countries are likely to sign a number of agreements as they are looking at enhancing cooperation in areas of shipping, counter-terrorism, renewable energy and taxatation.
A dinner will be hosted in honour of Modi which will be attended by top Belgian industrialists and political leaders.
After the summit, India and the European Union will come out with a joint statement and a separate document outlining the roadmap for next five years in the fields of political, security, energy and trade and investments.
A number of India-EU joint initiatives will be announced after the summit.
Asked about the long-pending FTA, Singla said there has been forward movement on a bumber of key issues. On the Italian marines issue, she said it is now under a UN tribunal for arbitration and that it no longer a bilateral issue.
About the Nuclear Security Summit, Amandeep Singh Gill, Joint Secretary (Disarmament) in the MEA said India expected that the the summit will raise "high-level awareness" about threat of nuclear terrorism and the need to strengthen a legally binding convention to deal with such
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