Polish Foreign Minister Radoslaw Sikorski, who burnished his credentials in the Ukraine crisis, is now in the spotlight over leaks in which he appears to criticize Polish-US ties and Britain's prime minister.

Poland recently floated the 51-year-old Oxford-educated former war correspondent to succeed Catherine Ashton, whose term as European Union foreign policy chief ends this year.

But remarks leaked on Monday by Poland's Wprost weekly attributed to Sikorski in a private conversation with former finance minister Jacek Rostowski could undermine his ambitions.

Sikorski, who is known for his hawkishness on Russia, allegedly said British Prime Minister David Cameron's concessions to euroskeptics showed his "incompetence in EU affairs".

"He should have said f--- off and tried to convince people and isolate the others (euroskeptics). But instead, he provided them with the means to humiliate him," he is heard telling Rostowski in the recording, purportedly made in a Warsaw restaurant earlier this year.

"It's either a very poorly thought-out move or, not for the first time, his incompetence in EU affairs."

He also characterized Warsaw's alliance with the US as "worthless, ... even harmful, because it gives Poland a false sense of security", according to the recordings, which were apparently made by waiters.

Sikorski has blasted the recordings as an "attack on the government by an organized criminal group".

His reputation for blunt talk has already earned him a spot on the 2012 Top Global Thinkers list compiled by Foreign Policy magazine for "telling the truth, even when it's not diplomatic".

But it is precisely this quality that has divided opinion over his bid to succeed Ashton.

"Sikorski is probably too strong a personality to head up Europe's diplomacy, an area in which member states want to retain strong influence," a diplomat in Brussels said on Tuesday on condition of anonymity.

Sikorski was defense minister in 2005-07 before taking over as chief diplomat, a job he has held in two successive center-right administrations led by Prime Minister Donald Tusk.

He played a high-profile role in the bloc's attempt to calm the Ukraine crisis in February.

He has also been a key advocate of the EU's Eastern Partnership program, which is designed to draw ex-Soviet states closer to the West.

Ukraine is the largest member of the group, which also includes Armenia, Azerbaijan, Belarus, Georgia and Moldova.

A correspondent for the British press in Angola and Afghanistan from 1986 to 1989, Sikorski spent two decades in Britain before returning to Poland.

The high-profile eavesdropping scandal has sparked a political crisis in Poland and called into question the future of its center-right government.

Tusk has dubbed the leaks an attempted "coup d'etat" aimed at "destabilizing" Poland.

Two people have been charged over them so far, including the manager of the restaurant in which Sikorski dined and a waiter at another upmarket eatery frequented by the capital's business elite.

Poland's leading Gazeta Wyborcza daily has suggested extortion could be the real motive behind the leaks, claiming three waiters at Warsaw's Sowa & Przyjaciele restaurant have been implicated.

(China Daily 06/26/2014 page10)