Anwar said his history with Mahathir was water under the bridge, as they shared the same goals of reforming the government and cleaning up a massive corruption scandal involving former Prime Minister Datuk Seri Najib Tun Razak.
"The search is supposed to be under the money laundering act. they found nothing incriminating", Najib's lawyer Harpal Singh Grewal told reporters who were camped outside the house.
This comes after a nighttime search at Mr Najib's home this week, when police seized personal items including several boxes of items like handbags, clothes and personal belongings as evidence, his lawyer said.
"This harassment has continued for nearly 18 hours and nothing meaningful has come from the search".
The police actions have fuelled speculation in Malaysia that Najib would soon be taken into custody, but so far there has been no indication that his arrest was imminent.
Malaysian police teams have raided two residences of former Prime Minister Najib Razak in Kuala Lumpur late on Wednesday, with searches still continuing into Thursday.
Najib has been accused of corruption and the mismanagement of 1MDB, which he established in 2009. But the amount of jewelry, he said, "is rather big".
Mr Najib has been embroiled in a multibillion-dollar scandal since 2015 after around US$700 million (S$932.8 million) - alleged to be 1MDB funds - appeared in his personal accounts before the election in 2013.
USA authorities said an estimated $4.5 billion has been embezzled from the fund by Low and his cronies, including Najib's stepson Riza Aziz, to spend on luxury condominiums in NY and London, fund Hollywood movies, and purchase jewelry and art pieces.
The government has set up a five-member committee, including a former attorney general and an adviser to Indonesia's Financial Services Authority, to handle the 1MDB case.
The convoy, which picked up vehicles as it sped through the city, carried the 70-year-old Anwar to the king's palace, where he shared a warm handshake with new Prime Minister Mahathir Mohamad - his former nemesis and current ally - before having an audience with the monarch. He has banned Najib from leaving the country. Police officials did not comment.
Mr. Najib and his wife, Rosmah Mansor, are at the center of a scandal over an estimated $7.5 billion that went missing from a government investment fund, 1Malyasia Development Berhad, which he oversaw.
His release follows last week's shocking result in the Malaysia's election, which saw Mahathir Mohamad, 92, oust the ruling party Barisan Nasional (BN) for the first time since the country became independent in 1957.
Malaysian politician Anwar Ibrahim has been freed from jail, paving the way for his return to politics.
Mahathir, who came out of retirement to lead the revolt against Najib, has signalled he will hand power to Anwar within two years.
An advocate for reform, clean government and an end to the previous government's authoritarian ways, Anwar made no immediate comment but was expected to address the public in the afternoon followed by a political rally in the evening.