The main rival to Turkey's President Recep Tayyip Erdogan has been formally arrested and charged with corruption.

Ekrem Imamoglu, the mayor of the Turkish city of Istanbul, is expected to be selected as the opposition Republican People's Party's (CHP) 2028 presidential candidate in a ballot on Sunday.

Hungarian Prime Minister Viktor Orbán’s peace efforts are gaining momentum recently. After meeting with President-elect Donald Trump at Mar-a-Lago, Florida, on Monday, Orbán held a telephone conversation with Russian President Vladimir Putin on Wednesday. The discussion focused on bilateral relations and the ongoing war in Ukraine.

Turkey suspended an arms treaty that imposed limits on conventional military equipment in Europe, joining NATO allies who did the same after Russia withdrew from the agreement last year.

President Recep Tayyip Erdogan signed a decree suspending Turkey’s obligations under the Treaty on Conventional Armed Forces in Europe, which was originally concluded during the Cold War, from April 8.

Turkey’s President Recep Tayyip Erdoğan suffered a major blow on Sunday, with initial results showing the country’s main opposition party notched up regional election victories around the country.

The opposition Republican People’s Party (CHP) held onto or captured the country’s five biggest cities in Sunday’s vote, which had been seen as a make-or-break moment for a movement still reeling from Erdoğan’s victory in the Turkish presidential contest in May 2023.

Turkey's main opposition party has claimed big election victories in the main cities of Istanbul and Ankara.

The results are a significant blow for Recep Tayyip Erdogan, who had hoped to regain control of the cities less than a year after he claimed a third term as president.

He led the campaign to win in Istanbul, where he grew up and became mayor.

But Ekrem Imamoglu, who first won the city in 2019, scored a second victory for the secular opposition CHP.

Recep Tayyip Erdogan and his party suffered their biggest upset in more than two decades on Sunday as the opposition swept municipal elections in Istanbul and other major cities.

The Republican People’s Party (CHP) retained mayoral seats in two key cities – Istanbul and the capital, Ankara.

The CHP also gained 15 new mayoral seats in cities across the country, advancing in locales that were previously strongholds of the Turkish president and his AK Party (AKP), marking the worst defeat since the latter came to power 21 years ago.

Hungary's parliamentary speaker said on Thursday there was no urgency in approving Sweden's NATO membership bid after ratification by Turkey left only Budapest holding up the lengthy accession process.

Turkey's general assembly, where President Tayyip Erdogan's ruling alliance holds a majority, voted 287-55 to approve the application that Sweden first made in 2022 to bolster its security in response to Russia's full-scale invasion of Ukraine.

Sen. Lindsey Graham, R-S.C., said Turkey is becoming "The Squad" of NATO after Turkish President Recep Tayyip Erdogan declared Israel a war criminal in its fight against Hamas terrorists.

The GOP senator made the comment Saturday in a post on X, the platform formerly known as Twitter.

"Seems that Turkey, particularly senior leadership, is setting itself up to be 'The Squad' of NATO," Graham wrote. "Very disappointing and destabilizing."

An explosion outside Turkey's interior ministry in the capital, Ankara, was a "terrorist attack", the interior minister has said.

Two attackers arrived in a commercial vehicle around 09:30 (06:30 GMT) and carried out the attack injuring two officers, Ali Yerlikaya said.

Mr Yerlikaya said an attacker blew himself up in front of a ministry building and another was "neutralised".

The explosion happened just hours before parliament was due to reconvene.

Turkish President Recep Tayyip Erdoğan said early on Saturday his Russian counterpart Vladimir Putin would visit Turkey next month and stressed his enthusiasm for peace talks in which Ankara could play a decisive role.

He made the remarks during a visit to Istanbul by Ukrainian President Volodymyr Zelenskyy, whom he greeted as his "dear friend."