Ukrainian President Volodymyr Zelenskiy says he aims to have all the elements of a peace plan ready in November so that Kyiv can convene a second, follow-up international summit on his vision for peace.
Ukraine held a first summit in Switzerland last month that was attended by representatives of 92 countries, but not Russia.
Kyiv has said it could invite representatives from Russia to the next one.
"I set a goal that in November we would have a fully ready plan," Zelenskiy told a news conference on Monday.
He made the remark in Kyiv after returning from a visit to Washington last week for a summit of the NATO military alliance more than 28 months since Russia's full-scale invasion.
A Russian deputy foreign minister said last week that Moscow would not attend the follow-up summit, although the Kremlin has been less categorical and said there was "no precise substance" regarding the idea of a second summit.
Ukraine has said the follow-up summit would discuss a plan that is devised by dozens of countries divided into working groups.
Zelenskiy also said Ukraine would receive some F-16 fighter jets this summer and more before the end of the year and that he could not disclose how many there would be exactly.
"There will not be enough. They will certainly strengthen us, but will there be enough of them to fight at a level with the Russian air force? I think they will not be enough. We are anticipating a larger quantity", he told reporters.