Brasilia, Sep 17 (IANS): A top Brazilian official has said it was not time for bravado, but for a mature diplomatic discussion on the matter of US espionage on Brazil.

Brazil is engaged in conversations with the US government on the matter and will act with maturity in this issue, Xinhua quoted Presidency Secretary General Gilberto Carvalho as saying.

Carvalho said Brazil would not give up its sovereignty.

"The people can be certain about one thing. President Dilma (Rousseff) will never renounce to the radical affirmation of our sovereignty," Carvalho said Monday.

He said Rousseff remains undecided on the matter of her state visit to Washington, scheduled for October.

The Brazilian president was allegedly personally targeted by the US global surveillance scheme, as were other government officials and the largest state-controlled company Petrobras.

The Brazilian government has demanded an official explanation on the scandal.

A trip for the team in charge of organising the president's visit was also cancelled.

Meanwhile, Liliana Ayalde, the new US ambassador to Brazil, arrived in Brasilia Monday.

At her first press conference, Ayalde declined to comment on the ongoing spying scandal.

Instead, she read out a statement highlighting the importance of Brazil-US relations and her hopes for strengthening those ties during her term.

"This is an important time in our relations, full of opportunities and possibilities. Together, I am sure we can expand and deepen the many ties between our two important and great nations. Over the next years, I hope to engage Brazil's government and people to build a stronger strategic partnership for the 21st century," Ayalde said.

Ayalde replaces Thomas Shannon after his three-year tenure as ambassador.

After revelations came to light in July that Washington's surveillance programme targeted Brazil in particular, Shannon was summoned by Brazil's Congress, but he declined, saying he was not authorised to discuss the matter.

The US maintains its spying programme aims to thwart terrorism, but Brazil alleges the real motive was industrial espionage, pointing to intercepted emails carrying sensitive data on Brazil's oil reserves.