David Cameron is prepared to support the Polish prime minister, Donald Tusk, as the new president of the European council as a counterweight to the incoming federalist European commission president, Jean-Claude Juncker.

The prime minister is set to tell fellow EU leaders at a summit in Brussels on Saturday that Tusk would be a strong candidate to lead a reform agenda in the EU. Cameron and Tusk, who has not yet announced his candidacy, discussed the summit in a phone call on Monday morning.

Britain suffered a setback on Monday when Juncker suggested that Lord Hill, the prime minister's candidate to be Britain's next European commissioner, would not secure an economics portfolio demanded by Downing Street. Sources close to Juncker told the Daily Telegraph that the incoming European commission president was disappointed by the failure of Britain and other EU member states to nominate a woman.

The British portfolio in the European commission will not be on the agenda for the summit on Saturday at which EU leaders will discuss a successor for Herman Van Rompuy, the European council president, and for Catherine Ashton, the EU foreign policy chief. Van Rompuy has chaired the meetings of EU heads of government and state since 2009.

Tusk has not yet declared his candidacy for the post. But Cameron believes that Tusk, who is from the centre right, would help balance the federalist instincts of Juncker. The prime minister also believes that it would be good for the leader of the largest of the new member states to take on such a major EU role.

Centre-left leaders are hoping that a leader from their group would assume the council presidency because Juncker also hails from the centre right. Helle Thorning-Schmidt, the Danish prime minister, has been linked to the post. Britain hopes that the centre left will settle for the foreign policy role which could go to Federica Mogherini, the Italian foreign minister.

Cameron's spokeswoman said Britain would support a candidate who is open to the prime minister's reform agenda. "Our overall objective, as we approach these discussions at Saturday's European council, will be making sure that we have a candidate that is willing to work with Britain to address our concerns in the coming years."

Cameron's support for his Polish counterpart shows that relations have been patched up between London and Warsaw after Tusk's spokesperson claimed that he had "fucked him [Cameron] up good" over plans to curb access to UK benefits. In the same set of recordings the Anglophile Polish foreign minister, Radoslaw Sikorski, said Cameron had "fucked up" Britain's relations with the EU by resorting to "stupid propaganda" to appease Eurosceptics.

The No 10 spokeswoman insisted that Tusk is open to British concerns. "Prime minister Tusk was clear that he thinks there are a number of reforms that need to be made in the EU and that is an agenda where he wants to work with the UK and other countries."