Qatari's emir congratulated former army chief  Abdel-Fattah El-Sisi Sunday after he was sworn in as president of Egypt, state news agency QNA reported.

QNA (Qatar News Agency) said Emir Sheikh Tamim Bin Hamad sent "a cable of congratulations" to  President El-Sisi on the occasion of his taking the oath as president of the "sisterly Arab Republic of Egypt."

Qatar's prime minister, Sheikh Abdullah Bin Nasser Al-Thani, also sent a congratulary telegram to the newly inaugurated president.

El-Sisi scored a landslide victory in last month's election, garnering approximately 97 percent of the vote.

El-Sisi was sworn in Sunday in a ceremony broadcast live on television and attended by a host of Arab royals and African leaders. Western allies, some of whom have voiced concerns about Egypt's progress to democracy, sent low-level officials or were represented by ambassadors.

Ties between Qatar and Egypt have been strained since the army's ouster of Islamist president Mohamed Morsi, who was strongly supported by Doha, last July on the back of mass protests against his yearlong rule.

Egypt singled out several countries — including Saudi Arabia, UAE, Palestine, Chad, Eritrea, and the US — with invitations to royals, parliament heads and senior government officials to attend the swearing-in ceremony and a following luncheon.

Qatar's ambassador to Cairo, Saif Moqadam Al-Boenain, was said to attend the ceremony upon a "protocol, traditional invitation to members of the diplomatic corps in Egypt," Nasser Kamel, a foreign ministry official, said.

Relations also deteriorated between Egypt and nearby Turkey which criticised Morsi's ouster and the government crackdown on his Muslim Brotherhood group.

Turkish foreign ministry officials said the country would be represented by its charge d'affaires in Cairo.