It is important that Malay-sians think seriously before renouncing their citizenship to take up residence in another country.

Deputy Prime Minister Tan Sri Muhyiddin Yassin said he knew of cases where they felt disheartened about certain things and moved elsewhere but later became homesick and wanted to return.

"Of course, they can re-apply for it but there is no guarantee that they can get back their citizenship as it is a serious matter," he said during a dialogue session with the Malaysian community in Italy on Tuesday.

Also present were Agriculture and Agro-based Industries Minister Datuk Seri Noh Omar and Malaysian Ambassador to Italy Ramli Naam.

"Once you renounce your citizenship, you have made a choice to become a citizen of another country," he added.

Muhyiddin, who is here to attend the World Summit on Food Security 2009, was replying to a question on whether the Government would consider reinstating the citizenship of former Malaysians.

He added that those who renounced their citizenship would have difficulty regaining them as they had, in the first instance, chosen to give it up and become nationals of another country.

Muhyiddin said it was their decision, and not the Government's, which they had made hopefully after taking into consideration many factors.

He, however, said Malaysians who had not given up their citizenship despite staying abroad for many years could come back and serve the country.

He urged those who had gained enough expertise overseas to return home under the Government's brain gain policy.

On another matter, Muhyiddin quipped about Malaysians "dying from over-eating" while children were dying of hunger in impoverished countries.

"In Malaysia, we don't have that problem. There are people who die of high blood pressure because they eat too much," he said in comparing the plight of poor countries whose people die of hunger.

Muhyiddin said he had, over the past few days, listened to the summit's heads of state and government relating their struggle to feed their hungry population.